Cancer Prevention in the Survivorship Setting.

OBJECTIVES: To describe how nurses can use risk reduction and health promotion activities to facilitate surveillance of late effects and secondary cancers in long-term cancer survivors. DATA SOURCES: Literature review on survivorship, nursing practice, cancer prevention, and survivorship; articles published in peer-reviewed scientific journals; and Web-based or professional organization resources. CONCLUSION: Appropriate participation in screening activities, early detection of cancer, and further advances in treatment have contributed to the rise in cancer survivors. A demand for nurses with clinical experience and competence in survivorship care will follow. IMPLICATIONS FOR NURSING PRACTICE: Oncology nurses have an essential role in providing safe and high-quality care throughout the survivorship experience, which can contribute to better long-term outcomes.

Efficient Preparation of Site-Specific Antibody-Drug Conjugates Using Phosphopantetheinyl Transferases.

Post-translational modification catalyzed by phosphopantetheinyl transferases (PPTases) has previously been used to site-specifically label proteins with structurally diverse molecules. PPTase catalysis results in covalent modification of a serine residue in acyl/peptidyl carrier proteins and their surrogate substrates which are typically fused to the N- or C-terminus. To test the utility of PPTases for preparing antibody-drug conjugates (ADCs), we inserted 11 and 12-mer PPTase substrate sequences at 110 constant region loop positions of trastuzumab. Using Sfp-PPTase, 63 sites could be efficiently labeled with an auristatin toxin, resulting in 95 homogeneous ADCs. ADCs labeled in the CH1 domain displayed in general excellent pharmacokinetic profiles and negligible drug loss. A subset of CH2 domain conjugates underwent rapid clearance in mouse pharmacokinetic studies. Rapid clearance correlated with lower thermal stability of the particular antibodies. Independent of conjugation site, almost all ADCs exhibited subnanomolar in vitro cytotoxicity against HER2-positive cell lines. One selected ADC was shown to induce tumor regression in a xenograft model at a single dose of 3 mg/kg, demonstrating that PPTase-mediated conjugation is suitable for the production of highly efficacious and homogeneous ADCs.

Changing Nursing Practice in Survivorship Care With Clinical Decision Tools.

The paradigm shift to include survivorship care as part of the cancer care continuum underscores the critical need for a change in nursing practice. One way to ensure that change in practice is delivered in a safe and efficient manner is through the use of clinical decision tools (CDTs). Such tools can be used to increase relevant knowledge and skills of nurses and patients. Despite the widespread recognition of their value, CDTs to educate providers on cancer survivors' care are limited and, when available, often are not used. Clinical practice algorithms were developed for disease-specific survivorship clinics in a cancer academic center. This article reviews the conceptual framework of the survivorship algorithms, describes the application of the algorithms in multidisciplinary disease-specific survivorship clinics, and discusses the implementation strategies used to promote clinicians' adoption and implementation of the algorithms. At a Glance • The authors found that algorithms can be successfully used as clinical decision tools(CDTs) to deliver survivorship care. • Algorithms and other CDTs are powerful tools to enhance professional practice. • Additional studies are needed to assess their effect on clinical practice and survivor outcomes.

Site-specific dual labeling of proteins by using small orthogonal tags at neutral pH.

To expand the utility of proteinaceous FRET biosensors, we have developed a dual-labeling approach based on two small bio-orthogonal tags: pyrroline-carboxy-lysine (Pcl) and the S6 peptide. The lack of cross-reactivity between those tags enables site-specific two-color protein conjugation in a one-pot reaction. Moreover, Pcl/S6 dual-tagged proteins can be produced in both bacterial and mammalian expression systems, as demonstrated for Z domain and IgE-Fc, respectively. Both proteins could be efficiently dual-labeled with FRET-compatible fluorescent dyes at neutral pH. In the case of IgE-Fc, the resulting conjugate enabled the monitoring of IgE binding to its high-affinity receptor FcεRI, which is a key event in allergic disease.

Improving wait time for chemotherapy in an outpatient clinic at a comprehensive cancer center.

PURPOSE: We conducted our study at the Ambulatory Treatment Center (ATC) of the MD Anderson Cancer Center, a network of six outpatient treatment units for patients receiving infusion therapies. Excessive patient wait time for chemotherapy was a primary source of ATC patient dissatisfaction. ATC employees expressed frustration, because often, patients arrived physically on time but were not treatment ready. Additionally, ATC staff emphasized challenges associated with obtaining finalized treatment orders for prescheduled appointments (ie, placeholder appointments without associated physician treatment orders). We aimed to decrease mean patient wait time from check-in to treatment in one ATC unit by 25%. METHODS: We studied appointment cycle time in the ATC Green Unit, stratifying appointments by type (ie, prescheduled [no finalized treatment orders] and scheduled [finalized treatment orders]). We obtained mean wait times at baseline (control) and again after our intervention period. We conducted interviews and observations in ATC Green, from which we developed a three-part plan to reduce wait time: increase process efficiency within ATC Green, enhance communications with MD Anderson clinics and centers, and incorporate information technology applications. RESULTS: After our intervention, we observed a 15% decrease in wait time for patients with prescheduled appointments and a 29% decrease for those with scheduled appointments. Overall, there was a 26.8% reduction in mean patient wait time relative to baseline (control). CONCLUSION: We observed a significantly decreased mean patient wait time after implementing our intervention. This decrease may improve patient satisfaction, relieve employee frustration with appointment scheduling, and create opportunities for increasing institutional revenue.

Site-specific protein modifications through pyrroline-carboxy-lysine residues.

Pyrroline-carboxy-lysine (Pcl) is a demethylated form of pyrrolysine that is generated by the pyrrolysine biosynthetic enzymes when the growth media is supplemented with D-ornithine. Pcl is readily incorporated by the unmodified pyrrolysyl-tRNA/tRNA synthetase pair into proteins expressed in Escherichia coli and in mammalian cells. Here, we describe a broadly applicable conjugation chemistry that is specific for Pcl and orthogonal to all other reactive groups on proteins. The reaction of Pcl with 2-amino-benzaldehyde or 2-amino-acetophenone reagents proceeds to near completion at neutral pH with high efficiency. We illustrate the versatility of the chemistry by conjugating Pcl proteins with poly(ethylene glycol)s, peptides, oligosaccharides, oligonucleotides, fluorescence, and biotin labels and other small molecules. Because Pcl is genetically encoded by TAG codons, this conjugation chemistry enables enhancements of the pharmacology and functionality of proteins through site-specific conjugation.

Phylogenetic analysis identifies many uncharacterized actin-like proteins (Alps) in bacteria: regulated polymerization, dynamic instability and treadmilling in Alp7A.

Actin, one of the most abundant proteins in the eukaryotic cell, also has an abundance of relatives in the eukaryotic proteome. To date though, only five families of actins have been characterized in bacteria. We have conducted a phylogenetic search and uncovered more than 35 highly divergent families of actin-like proteins (Alps) in bacteria. Their genes are found primarily on phage genomes, on plasmids and on integrating conjugative elements, and are likely to be involved in a variety of functions. We characterize three Alps and find that all form filaments in the cell. The filaments of Alp7A, a plasmid partitioning protein and one of the most divergent of the Alps, display dynamic instability and also treadmill. Alp7A requires other elements from the plasmid to assemble into dynamic polymers in the cell. Our findings suggest that most if not all of the Alps are indeed actin relatives, and that actin is very well represented in bacteria.

Treadmilling of a prokaryotic tubulin-like protein, TubZ, required for plasmid stability in Bacillus thuringiensis.

Prokaryotes rely on a distant tubulin homolog, FtsZ, for assembling the cytokinetic ring essential for cell division, but are otherwise generally thought to lack tubulin-like polymers that participate in processes such as DNA segregation. Here we characterize a protein (TubZ) from the Bacillus thuringiensis virulence plasmid pBtoxis, which is a member of the tubulin/FtsZ GTPase superfamily but is only distantly related to both FtsZ and tubulin. TubZ assembles dynamic, linear polymers that exhibit directional polymerization with plus and minus ends, movement by treadmilling, and a critical concentration for assembly. A point mutation (D269A) that alters a highly conserved catalytic residue within the T7 loop completely eliminates treadmilling and allows the formation of stable polymers at a much lower protein concentration than the wild-type protein. When expressed in trans, TubZ(D269A) coassembles with wild-type TubZ and significantly reduces the stability of pBtoxis, demonstrating a direct correlation between TubZ dynamics and plasmid maintenance. The tubZ gene is in an operon with tubR, which encodes a putative DNA-binding protein that regulates TubZ levels. Our results suggest that TubZ is representative of a novel class of prokaryotic cytoskeletal proteins important for plasmid stability that diverged long ago from the ancient tubulin/FtsZ ancestor.

Variability in aflatoxin B(1)-macromolecular binding and relationship to biotransformation enzyme expression in human prenatal and adult liver.

Studies of transplacental transfer of aflatoxin B(1) (AFB(1)) suggest that the developing human fetus may be a sensitive target for AFB(1) injury. Because AFB(1) requires metabolic activation to the reactive AFB(1)-8,9-exo-epoxide (AFBO) to exert its carcinogenic effects, ontogenic and interindividual differences in AFB(1) biotransformation enzymes may underlie susceptibility to AFB(1)-induced cell injury. The present study was initiated to compare the rates of in vitro AFB(1)-DNA and AFB(1)-protein adduct formation among a panel of 10 adult and 10 second-trimester prenatal livers and to examine the relationship among AFB(1) metabolizing enzyme expression and AFB(1) binding. Mixtures of cytosolic and microsomal proteins from prenatal and adult livers catalyzed the formation of AFB(1)-DNA and AFB(1)-protein adducts at relatively similar rates, although greater individual variability in AFB(1) adduct formation was observed in adult tissues. Extensive interindividual variation among adult tissues was observed in the expression of the AFB(1) activation enzymes cytochrome P4501A2 (CYP1A2), CYP3A4/5, and lipoxygenase (LO). Prenatal CYP3A7 expression was also highly variable. LO expression was eightfold higher in prenatal liver tissues than adults, whereas the expression of the AFBO detoxification enzyme microsomal epoxide hydrolase was twofold higher in adult liver. The levels of the polymorphic glutathione S-transferase M1 (hGSTM1-1), which may potentially protect against AFBO injury, were higher in the hGSTM1-1-expressing tissues of adults in relation to prenatal livers. In general, there was not a strong relationship among AFB(1)-DNA or AFB(1)-protein adduct formation and expression levels of individual AFB(1) metabolizing enzymes. In summary, despite the presence of marked individual and ontogenic differences in the expression of AFB(1) metabolizing enzymes, human second trimester prenatal liver tissues compared to adults do not exhibit a marked sensitivity to the in vitro formation of macromolecular AFB(1) adducts.