A molecularly engineered lectin destroys EGFR and inhibits the growth of non-small cell lung cancer.

Survival rates for non-small cell lung cancer (NSCLC) remain low despite the advent of novel therapeutics. Tyrosine kinase inhibitors (TKIs) targeting mutant epidermal growth factor receptor (EGFR) in NSCLC have significantly improved mortality but are plagued with challenges--they can only be used in the small fraction of patients who have susceptible driver mutations, and resistance inevitably develops. Aberrant glycosylation on the surface of cancer cells is an attractive therapeutic target as these abnormal glycosylation patterns are typically specific to cancer cells and are not present on healthy cells. H84T BanLec (H84T), a lectin previously engineered by our group to separate its antiviral activity from its mitogenicity, exhibits precision binding of high mannose, an abnormal glycan present on the surface of many cancer cells, including NSCLC. Here, we show that H84T binds to and inhibits the growth of diverse NSCLC cell lines by inducing lysosomal degradation of EGFR and leading to cancer cell death through autophagy. This is a mechanism distinct from EGFR TKIs and is independent of EGFR mutation status; H84T inhibited proliferation of both cell lines expressing wild type EGFR and those expressing mutant EGFR that is resistant to all TKIs. Further, H84T binds strongly to multiple and diverse clinical samples of both pulmonary adenocarcinoma and squamous cell carcinoma. H84T is thus a promising potential therapeutic in NSCLC, with the ability to circumvent the challenges currently faced by EGFR TKIs.

The role of the histone H3 variant CENPA in prostate cancer.

Overexpression of centromeric proteins has been identified in a number of human malignancies, but the functional and mechanistic contributions of these proteins to disease progression have not been characterized. The centromeric histone H3 variant centromere protein A (CENPA) is an epigenetic mark that determines centromere identity. Here, using an array of approaches, including RNA-sequencing and ChIP-sequencing analyses, immunohistochemistry-based tissue microarrays, and various cell biology assays, we demonstrate that CENPA is highly overexpressed in prostate cancer in both tissue and cell lines and that the level of CENPA expression correlates with the disease stage in a large cohort of patients. Gain-of-function and loss-of-function experiments confirmed that CENPA promotes prostate cancer cell line growth. The results from the integrated sequencing experiments suggested a previously unidentified function of CENPA as a transcriptional regulator that modulates expression of critical proliferation, cell-cycle, and centromere/kinetochore genes. Taken together, our findings show that CENPA overexpression is crucial to prostate cancer growth.

Ruxolitinib in adult patients with secondary haemophagocytic lymphohistiocytosis: an open-label, single-centre, pilot trial.

BACKGROUND: Hemophagocytic lymphohistiocytosis is a cytokine-driven inflammatory syndrome that is associated with substantial morbidity and mortality. Overall survival in adult patients with secondary haemophagocytic lymphohistiocytosis remains suboptimal, and novel therapeutic strategies are needed. The phosphorylation-dependent activation of the Janus family kinases JAK1 and JAK2 are hallmarks of the final common pathway in this disease. We therefore aimed to determine the activity and safety of ruxolitinib, a JAK inhibitor, in adults with secondary haemophagocytic lymphohistiocytosis. METHODS: We performed an open-label, single-centre, pilot study of ruxolitinib in adults with secondary haemophagocytic lymphohistiocytosis at the University of Michigan Rogel Cancer Center (Ann Arbor, MI, USA). We included patients aged 18 years or more who fulfilled at least five of the eight HLH-2004 criteria for hemophagocytic lymphohistiocytosis. Discontinuation of corticosteroids was not required for enrolment in this study. Patients received oral ruxolitinib (15 mg twice a day) on a continuous 28-day cycle, or until disease progression or unacceptable toxicity. The primary endpoint was overall survival at 2 months from the first dose of ruxolitinib. Secondary endpoints included the assessment of adverse events, response (defined as the assessment of all quantifiable signs and laboratory abnormalities included in the diagnostic criteria for haemophagocytic lymphohistiocytosis), and pharmacodynamic biomarkers. Analyses were done in all treated patients with available data. This study is registered with ClinicalTrials.gov, number NCT02400463, and is still recruiting. FINDINGS: As of Feb 7, 2019, five patients had been enrolled. The first patient was enrolled in February, 2016. No deaths were recorded, with a median follow-up of 490 days (IQR 190-1075). 2-month overall survival was 100% (95% CI 57-100). Regarding response, resolution of symptoms (either partial or complete) and disease-associated laboratory abnormalities was observed in all five patients. Cytopenias improved in all patients within the first week of treatment, leading to relatively rapid transfusion independence, discontinuation of corticosteroids, and hospital discharge. A single serious adverse event (ie, grade 4 febrile neutropenia) was reported. One patient discontinued treatment because of grade 2 extremity pain and no treatment-related deaths were observed. Improvements in inflammatory markers (eg, ferritin, soluble IL-2 receptor) and T cells and monocytes activation (ie, decreased STAT1 phosphorylation) were observed following treatment. INTERPRETATION: These preliminary data suggest that ruxolitinib is active, well tolerated, and manageable in the outpatient setting in patients with secondary haemophagocytic lymphohistiocytosis. Given the paucity of effective, non-myelosuppressive therapies, these preliminary findings have important therapeutic implications for patients with haemophagocytic lymphohistiocytosis and other cytokine-release syndromes and warrant further investigation. FUNDING: National Cancer Institute, the University of Michigan Rogel Cancer Center, and Incyte Corporation.

Structural variation of centromeric endogenous retroviruses in human populations and their impact on cutaneous T-cell lymphoma, Sézary syndrome, and HIV infection.

BACKGROUND: Human Endogenous Retroviruses type K HML-2 (HK2) are integrated into 117 or more areas of human chromosomal arms while two newly discovered HK2 proviruses, K111 and K222, spread extensively in pericentromeric regions, are the first retroviruses discovered in these areas of our genome. METHODS: We use PCR and sequencing analysis to characterize pericentromeric K111 proviruses in DNA from individuals of diverse ethnicities and patients with different diseases. RESULTS: We found that the 5' LTR-gag region of K111 proviruses is missing in certain individuals, creating pericentromeric instability. K111 deletion (-/- K111) is seen in about 15% of Caucasian, Asian, and Middle Eastern populations; it is missing in 2.36% of African individuals, suggesting that the -/- K111 genotype originated out of Africa. As we identified the -/-K111 genotype in Cutaneous T-cell lymphoma (CTCL) cell lines, we studied whether the -/-K111 genotype is associated with CTCL. We found a significant increase in the frequency of detection of the -/-K111 genotype in Caucasian patients with severe CTCL and/or Sézary syndrome (n = 35, 37.14%), compared to healthy controls (n = 160, 15.6%) [p = 0.011]. The -/-K111 genotype was also found to vary in HIV-1 infection. Although Caucasian healthy individuals have a similar frequency of detection of the -/- K111 genotype, Caucasian HIV Long-Term Non-Progressors (LTNPs) and/or elite controllers, have significantly higher detection of the -/-K111 genotype (30.55%; n = 36) than patients who rapidly progress to AIDS (8.5%; n = 47) [p = 0.0097]. CONCLUSION: Our data indicate that pericentromeric instability is associated with more severe CTCL and/or Sézary syndrome in Caucasians, and appears to allow T-cells to survive lysis by HIV infection. These findings also provide new understanding of human evolution, as the -/-K111 genotype appears to have arisen out of Africa and is distributed unevenly throughout the world, possibly affecting the severity of HIV in different geographic areas.

The American Society of Hematology (ASH) Medical Educators Institute: a Pilot Faculty Development Project for Hematology Educators.

Clinician educators at academic medical centers often lack the community, mentorship, and faculty development to support their missions around education scholarship and teaching. Inadequate support for clinician educators can lead to professional dissatisfaction and slowed academic advancement. In 2014, ASH conducted a needs assessment of medical school hematology course directors, hematology-oncology fellowship program directors, and other ASH members identified as educators to determine this community's desire for faculty development in medical education. These data furthered the development of an annual faculty development program for hematology educators offering an interactive curriculum and support for an educational scholarly project. The needs assessment indicated that over 70% of respondents would be personally interested in a faculty development opportunity for hematology educators and only 11% had previously participated in such a program. A steering committee designed an intervention blending didactics, interactive small group exercises, webinars, mentorship for a scholarly project, 360-degree feedback for each participant, and a forum to discuss common career development goals. Of 42 applicants, 20 participants were chosen for the inaugural workshop. Following successful execution of the workshop, participants reported significant increase in confidence in the knowledge, skills, and attitudes targeted by the curriculum. A series of follow-up webinars have been developed to deliver additional content not covered during the workshop and to continue mentorship relationships. The curriculum will be further refined based on feedback from faculty and participants. Long-term outcome measurement will include tracking all participants' publications and presentations, time to promotion, and involvement in national medical education initiatives.

Determinants of hematology-oncology trainees' postfellowship career pathways with a focus on nonmalignant hematology.

Nonmalignant hematologic conditions are extremely prevalent and contribute significantly to the global burden of disease. The US health care system may soon face a shortage of specialists in nonmalignant hematology. We sought to identify factors that lead hematology-oncology fellows to pursue (or not to pursue) careers in nonmalignant hematology. Cross-sectional, web-based survey distributed to 149 graduates of a hematology-oncology fellowship program at a large academic medical center between 1998 and 2016. Eighty-six out of 149 graduates responded (57.7%); most (59 [68.6%]) practice at an academic medical center. Respondents spend a mean of 61% of their time in clinical practice, 23.7% conducting research, 5.2% in education, and 5.2% in administration. Those in clinical practice spend a mean of 52.1% of their time in solid tumor oncology, 37.5% in hematologic malignancies, and 10% in nonmalignant hematology; only 1 spent >50% of time practicing nonmalignant hematology. Factors most significantly affecting choice of patient population included clinical experience during fellowship and intellectual stimulation of the patient population/disease type. Factors that could have most significantly influenced a decision to spend more time in nonmalignant hematology included increased exposure/access to role models and mentors and opportunities for better career growth/advancement. Fellowship graduates spend >50% of their time in clinical practice, but almost none spend a significant amount of time practicing nonmalignant hematology. Given the growing number of patients with nonmalignant hematologic conditions and a possible future provider shortage, medical trainees should be encouraged to pursue careers in nonmalignant hematology.

Competency-Based Medical Education in the Internal Medicine Clerkship: A Report From the Alliance for Academic Internal Medicine Undergraduate Medical Education Task Force.

As medical educators continue to redefine learning and assessment across the continuum, implementation of competency-based medical education in the undergraduate setting has become a focus of many medical schools. While standards of competency have been defined for the graduating student, there is no uniform approach for defining competency expectations for students during their core clerkship year. The authors describe the process by which an Alliance for Academic Internal Medicine task force developed a paradigm for competency-based assessment of students during their inpatient internal medicine (IM) clerkship. Building on work at the resident and fellowship levels, the task force focused on the development of key learning outcomes as defined by entrustable professional activities (EPAs) that were specific to educational experiences on the IM clerkship, as well as identification of high-priority assessment domains. The work was informed by a national survey of clerkship directors.Six key EPAs emerged: generating a differential diagnosis, obtaining a complete and accurate history and physical exam, obtaining focused histories and clinically relevant physical exams, preparing an oral presentation, interpreting the results of basic diagnostic studies, and providing well-organized clinical documentation. A model for assessment was proposed, with descriptors aligned to the scale of supervision and mapped to Accreditation Council for Graduate Medical Education domains of competence. The proposed paradigm offers a standardized template that may be used across IM clerkships, and which would effectively bridge competency evaluation in the clerkship to fourth-year assessment as well as eventual postgraduate training.

For Residents and Fellows: What to Look for in a Laboratory Research Mentor.

Preparing for a laboratory or research-based career in academic medicine involves learning and acquiring a broad set of knowledge, skills, and experiences that facilitate the transition from trainee to faculty member. It also involves identifying and cultivating solid mentor/mentee relationships in the laboratory environment. It is well known that different skill sets and mentoring approaches are necessary for those pursuing laboratory-based research as compared with those needed for clinical practice and patient-oriented research. Here, we discuss several key approaches to help mentees identify fruitful mentor/mentee relationships.

Medical Knowledge Assessment by Hematology and Medical Oncology In-Training Examinations Are Better Than Program Director Assessments at Predicting Subspecialty Certification Examination Performance.

The Accreditation Council for Graduate Medical Education's Next Accreditation System requires training programs to demonstrate that fellows are achieving competence in medical knowledge (MK), as part of a global assessment of clinical competency. Passing American Board of Internal Medicine (ABIM) certification examinations is recognized as a metric of MK competency. This study examines several in-training MK assessment approaches and their ability to predict performance on the ABIM Hematology or Medical Oncology Certification Examinations. Results of a Hematology In-Service Examination (ISE) and an Oncology In-Training Examination (ITE), program director (PD) ratings, demographic variables, United States Medical Licensing Examination (USMLE), and ABIM Internal Medicine (IM) Certification Examination were compared. Stepwise multiple regression and logistic regression analyses evaluated these assessment approaches as predictors of performance on the Hematology or Medical Oncology Certification Examinations. Hematology ISE scores were the strongest predictor of Hematology Certification Examination scores (ß = 0.41) (passing odds ratio [OR], 1.012; 95 % confidence interval [CI], 1.008-1.015), and the Oncology ITE scores were the strongest predictor of Medical Oncology Certification Examination scores (ß = 0.45) (passing OR, 1.013; 95 % CI, 1.011-1.016). PD rating of MK was the weakest predictor of Medical Oncology Certification Examination scores (ß = 0.07) and was not significantly predictive of Hematology Certification Examination scores. Hematology and Oncology ITEs are better predictors of certification examination performance than PD ratings of MK, reinforcing the effectiveness of ITEs for competency-based assessment of MK.

Optimizing the post-graduate institutional program evaluation process.

BACKGROUND: Reviewing program educational efforts is an important component of postgraduate medical education program accreditation. The post-graduate review process has evolved over time to include centralized oversight based on accreditation standards. The institutional review process and the impact on participating faculty are topics not well described in the literature. METHODS: We conducted multiple Plan-Do-Study-Act (PDSA) cycles to identify and implement areas for change to improve productivity in our institutional program review committee. We also conducted one focus group and six in-person interviews with 18 committee members to explore their perspectives on the committee's evolution. One author (MLL) reviewed the transcripts and performed the initial thematic coding with a PhD level research associate and identified and categorized themes. These themes were confirmed by all participating committee members upon review of a detailed summary. Emergent themes were triangulated with the University of Michigan Medical School's Admissions Executive Committee (AEC). RESULTS: We present an overview of adopted new practices to the educational program evaluation process at the University of Michigan Health System that includes standardization of meetings, inclusion of resident members, development of area content experts, solicitation of committed committee members, transition from paper to electronic committee materials, and focus on continuous improvement. Faculty and resident committee members identified multiple improvement areas including the ability to provide high quality reviews of training programs, personal and professional development, and improved feedback from program trainees. CONCLUSIONS: A standing committee that utilizes the expertise of a group of committed faculty members and which includes formal resident membership has significant advantages over ad hoc or other organizational structures for program evaluation committees.

The effect of an intense mentoring program on junior investigators' preparation for a patient-oriented clinical research career.

PROBLEM: There is a recognized need to translate scientific discoveries to patient-oriented clinical research (POCR). Several obstacles interfere with the successful recruitment and retention of physicians for POCR careers. APPROACH: The American Society of Hematology developed a yearlong educational and mentoring experience, the Clinical Research Training Institute (CRTI), for early-career physician-scientists from multiple institutions throughout the United States and Canada pursuing POCR careers. Several academic outcome measures of the 140 participants in the first seven years (2003-2010) of CRTI were evaluated by reviewing former trainee participants' curriculum vitae and survey responses. OUTCOMES: Ethnic, racial, and gender diversity of CRTI trainees was reflective of the proportions represented across U.S. hematology/oncology fellowship programs. Eighty-six percent (109/126) of trainees reported success establishing a POCR study; nearly half (62/126) had primarily research-focused jobs. Former CRTI trainees received at least 262 external grant awards and published 1,035 peer-reviewed manuscripts, 173 chapters, and 115 review articles. NEXT STEPS: Because mentorship is key to developing a successful career, the CRTI program is being modified to enhance longitudinal mentorship by CRTI faculty mentors and mentors at trainees' home institutions, as well as to encourage the establishment of collaborations and the potential for research project success. Efforts to make the CRTI experience available to more phy sicians, include more CRTI graduates as faculty, and increase participation by hematologists from backgrounds under represented in medicine are under way.

Human Endogenous Retrovirus Type K (HERV-K) Particles Package and Transmit HERV-K-Related Sequences.

UNLABELLED: Human endogenous retroviruses (HERV) make up 8% of the human genome. While the youngest of these retroviruses, HERV-K(HML-2), termed HK2, is able to code for all viral proteins and produce virus-like particles, it is not known if these virus particles package and transmit HK2-related sequences. Here, we analyzed the capacity of HK2 for packaging and transmitting HK2 sequences. We created an HK2 probe, termed Bogota, which can be packaged into HK2 viruses, and transfected it into cells that make HK2 particles. Supernatants of the transfected cells, which contained HK2 viral particles, then were added to target cells, and the transmissibility of the HK2 Bogota reporter was tracked by G418 resistance. Our studies revealed that contemporary HK2 virions produced by some teratocarcinoma and breast cancer cell lines, as well as by peripheral blood lymphocytes from lymphoma patients, can package HK2 Bogota probes, and these viruses transmitted these probes to other cells. After transmission, HK2 Bogota transcripts undergo reverse transcription, a step impaired by antiretroviral agents or by introduction of mutations into the probe sequences required for reverse transcription. HK2 viruses were more efficiently transmitted in the presence of HK2 Rec or HIV-1 Tat and Vif. Transmitted Bogota probes formed episomes but did not integrate into the cellular genome. Resistance to integration might explain the relatively low number of HK2 insertions that were acquired during the last 25 million years of evolution. Whether transient transmission of modern HK2 sequences, which encode two putative oncoproteins, can lead to disease remains to be studied. IMPORTANCE: Retroviruses invaded the genome of human ancestors over the course of millions of years, yet these viruses generally have been inactivated during evolution, with only remnants of these infectious sequences remaining in the human genome. One of these viruses, termed HK2, still is capable of producing virus particles, although these particles have been regarded as being noninfectious. Using a genetic probe derived from HK2, we have discovered that HK2 viruses produced in modern humans can package HK2 sequences and transmit them to various other cells. Furthermore, the genetic sequences packaged in HK2 undergo reverse transcription. The transmitted probe circularized in the cell and failed to integrate into the cellular genome. These findings suggest that modern HK2 viruses can package viral RNA and transmit it to other cells. Contrary to previous views, we provide evidence of an extracellular viral phase of modern HK2 viruses. We have no evidence of sustained, spreading infection.

Preclinical Medical Student Hematology/Oncology Education Environment.

To better prepare medical students to care for patients in today's changing health-care environment as they transition to continuing their education as residents, many US medical schools have been reviewing and modifying their curricula and are considering integration of newer adult learning techniques, including team-based learning, flipped classrooms, and other active learning approaches (Assoc Am Med Coll. 2014). Directors of hematology/oncology (H/O) courses requested an assessment of today's H/O education environment to help them respond to the ongoing changes in the education content and environment that will be necessary to meet this goal. Several recommendations for the improvement of cancer education resulted from American Association for Cancer Education's (ACCE's) "Cancer Education Survey II" including a call for medical schools to evaluate the effectiveness of current teaching methods in achieving cancer education objectives (Chamberlain et al. J Cancer Educ 7(2):105-114.2014). To understand the current environment and resources used in medical student preclinical H/O courses, an Internet-based, Survey Monkey®-formatted, questionnaire focusing on nine topic areas was distributed to 130 United States Hematology/Oncology Course Directors (HOCDs). HOCDs represent a diverse group of individuals who work in variably supportive environments and who are variably satisfied with their position. Several aspects of these courses remain relatively unchanged from previous assessments, including a predominance of traditional lectures, small group sessions, and examinations that are either written or computer-based. Newer technology, including web-based reproduction of lectures, virtual microscopes, and availability of additional web-based content has been introduced into these courses. A variety of learner evaluation and course assessment approaches are used. The ultimate effectiveness and impact of these changes needs to be determined.

Challenges in Measuring Benefit of Clinical Research Training Programs--the ASH Clinical Research Training Institute Example.

The American Society of Hematology developed the Clinical Research Training Institute (CRTI) to address the lack of training in patient-oriented research among hematologists. As the program continues, we need to consider metrics for measuring the benefits of such a training program. This article addresses the benefits of clinical research training programs. The fundamental and key components are education and mentorship. However, there are several other benefits including promotion of collaboration, job and advancement opportunities, and promotion of work-life balance. The benefits of clinical research training programs need to be measured so that funders and society can judge if they are worth the investment in time and resources. Identification of elements that are important to program benefit is essential to measuring the benefit of the program as well as program planning. Future work should focus on the constructs which contribute to benefits of clinical research training programs such as CRTI.

Genomic flexibility of human endogenous retrovirus type K.

UNLABELLED: Human endogenous retrovirus type K (HERV-K) proviruses are scattered throughout the human genome, but as no infectious HERV-K virus has been detected to date, the mechanism by which these viruses replicated and populated the genome remains unresolved. Here, we provide evidence that, in addition to the RNA genomes that canonical retroviruses package, modern HERV-K viruses can contain reverse-transcribed DNA (RT-DNA) genomes. Indeed, reverse transcription of genomic HERV-K RNA into the DNA form is able to occur in three distinct times and locations: (i) in the virus-producing cell prior to viral release, yielding a DNA-containing extracellular virus particle similar to the spumaviruses; (ii) within the extracellular virus particle itself, transitioning from an RNA-containing particle to a DNA-containing particle; and (iii) after entry of the RNA-containing virus into the target cell, similar to canonical retroviruses, such as murine leukemia virus and HIV. Moreover, using a resuscitated HERV-K virus construct, we show that both viruses with RNA genomes and viruses with DNA genomes are capable of infecting target cells. This high level of genomic flexibility historically could have permitted these viruses to replicate in various host cell environments, potentially assisting in their many integration events and resulting in their high prevalence in the human genome. Moreover, the ability of modern HERV-K viruses to proceed through reverse transcription and package RT-DNA genomes suggests a higher level of replication competency than was previously understood, and it may be relevant in HERV-K-associated human diseases. IMPORTANCE: Retroviral elements comprise at least 8% of the human genome. Of all the endogenous retroviruses, HERV-K viruses are the most intact and biologically active. While a modern infectious HERV-K has yet to be found, HERV-K activation has been associated with cancers, autoimmune diseases, and HIV-1 infection. Thus, determining how this virus family became such a prevalent member of our genome and what it is capable of in its current form are of the utmost importance. Here, we provide evidence that HERV-K viruses currently found in the human genome are able to proceed through reverse transcription and historically utilized a life cycle with a surprising degree of genomic flexibility in which both RNA- and DNA-containing viruses were capable of mediating infection.

Regulation of the human endogenous retrovirus K (HML-2) transcriptome by the HIV-1 Tat protein.

UNLABELLED: Approximately 8% of the human genome is made up of endogenous retroviral sequences. As the HIV-1 Tat protein activates the overall expression of the human endogenous retrovirus type K (HERV-K) (HML-2), we used next-generation sequencing to determine which of the 91 currently annotated HERV-K (HML-2) proviruses are regulated by Tat. Transcriptome sequencing of total RNA isolated from Tat- and vehicle-treated peripheral blood lymphocytes from a healthy donor showed that Tat significantly activates expression of 26 unique HERV-K (HML-2) proviruses, silences 12, and does not significantly alter the expression of the remaining proviruses. Quantitative reverse transcription-PCR validation of the sequencing data was performed on Tat-treated PBLs of seven donors using provirus-specific primers and corroborated the results with a substantial degree of quantitative similarity. IMPORTANCE: The expression of HERV-K (HML-2) is tightly regulated but becomes markedly increased following infection with HIV-1, in part due to the HIV-1 Tat protein. The findings reported here demonstrate the complexity of the genome-wide regulation of HERV-K (HML-2) expression by Tat. This work also demonstrates that although HERV-K (HML-2) proviruses in the human genome are highly similar in terms of DNA sequence, modulation of the expression of specific proviruses in a given biological situation can be ascertained using next-generation sequencing and bioinformatics analysis.

HIV infection reveals widespread expansion of novel centromeric human endogenous retroviruses.

Human endogenous retroviruses (HERVs) make up 8% of the human genome. The HERV-K (HML-2) family is the most recent group of these viruses to have inserted into the genome, and we have detected the activation of HERV-K (HML-2) proviruses in the blood of patients with HIV-1 infection. We report that HIV-1 infection activates expression of a novel HERV-K (HML-2) provirus, termed K111, present in multiple copies in the centromeres of chromosomes throughout the human genome yet not annotated in the most recent human genome assembly. Infection with HIV-1 or stimulation with the HIV-1 Tat protein leads to the activation of K111 proviruses. K111 is present as a single copy in the genome of the chimpanzee, yet K111 is not found in the genomes of other primates. Remarkably, K111 proviruses appear in the genomes of the extinct Neanderthal and Denisovan, while modern humans have at least 100 K111 proviruses spread across the centromeres of 15 chromosomes. Our studies suggest that the progenitor K111 integrated before the Homo-Pan divergence and expanded in copy number during the evolution of hominins, perhaps by recombination. The expansion of K111 provides sequence evidence suggesting that recombination between the centromeres of various chromosomes took place during the evolution of humans. K111 proviruses show significant sequence variations in each individual centromere, which may serve as markers in future efforts to annotate human centromere sequences. Further, this work is an example of the potential to discover previously unknown genomic sequences through the analysis of nucleic acids found in the blood of patients.

Characterization of human endogenous retroviral elements in the blood of HIV-1-infected individuals.

We previously reported finding the RNA of a type K human endogenous retrovirus, HERV-K (HML-2), at high titers in the plasma of HIV-1-infected and cancer patients (R. Contreras-Galindo et al., J. Virol. 82:9329-9236, 2008.). The extent to which the HERV-K (HML-2) proviruses become activated and the nature of their activated viral RNAs remain important questions. Therefore, we amplified and sequenced the full-length RNA of the env gene of the type 1 and 2 HERV-K (HML-2) viruses collected from the plasma of seven HIV-1-infected patients over a period of 1 to 3 years and from five breast cancer patients in order to reconstruct the genetic evolution of these viruses. HERV-K (HML-2) RNA was found in plasma fractions of HIV-1 patients at a density of ∼1.16 g/ml that contained both immature and correctly processed HERV-K (HML-2) proteins and virus-like particles that were recognized by anti-HERV-K (HML-2) antibodies. RNA sequences from novel HERV-K (HML-2) proviruses were discovered, including K111, which is specifically active during HIV-1 infection. Viral RNA arose from complete proviruses and proviruses devoid of a 5' long terminal repeat, suggesting that the expression of HERV-K (HML-2) RNA in these patients may involve sense and antisense transcription. In HIV-1-infected individuals, the HERV-K (HML-2) viral RNA showed evidence of frequent recombination, accumulation of synonymous rather than nonsynonymous mutations, and conserved N-glycosylation sites, suggesting that some of the HERV-K (HML-2) viral RNAs have undergone reverse transcription and are under purifying selection. In contrast, HERV-K (HML-2) RNA sequences found in the blood of breast cancer patients showed no evidence of recombination and exhibited only sporadic viral mutations. This study suggests that HERV-K (HML-2) is active in HIV-1-infected patients, and the resulting RNA message reveals previously undiscovered HERV-K (HML-2) genomic sequences.

L-Asparaginase encapsulated intact erythrocytes for treatment of acute lymphoblastic leukemia (ALL).

As a primary drug for the treatment of acute lymphoblastic leukemia (ALL), encapsulation of L-asparaginase (ASNase) into red blood cells (RBC) has been popular to circumvent immunogenicity from the exogenous protein. Unlike existing methods that perturbs RBC membranes, we introduce a novel method of RBC-incorporation of proteins using the membrane-translocating low molecular weight protamine (LMWP). Confocal study of fluorescence-labeled LMWP-ovalbumin, as a model protein conjugate, has shown significant fluorescence inside RBCs. Surface morphology by scanning electron microscopy of the RBCs loaded with LMWP-ASNase was indistinguishable with normal RBCs. These drug loaded RBCs also closely resembled the profile of the native erythrocytes in terms of osmotic fragility, oxygen dissociation and hematological parameters. The in vivo half-life of enzyme activity after administering 8 units of RBC/LMWP-ASNase in DBA/2 mice was prolonged to 4.5+/-0.5 days whereas that of RBCs loaded with ASNase via a hypotonic method was 2.4+/-0.7 days. Furthermore, the mean survival time of DBA/2 mice bearing mouse lymphoma cell L5178Y was improved by approximately 44% compared to the saline control group after treatment with the RBC loaded enzymes. From these data, an innovative, novel method for encapsulating proteins into intact and fully functional erythrocytes was established for potential treatment of ALL.