Early Introduction of Dermatology Clinical Skills in Medical Training

BACKGROUND

Skin diseases are among the most common diseases encountered by healthcare professionals. Despite this, dedicated dermatology teaching is limited in most Canadian medical school training programs. This is especially true of clinical skills training.

OBJECTIVES

To determine the impact of early introduction of dermatology clinical skills in Canadian undergraduate medical training. Secondary objectives included examining the impact of having sessions co-led by a clinician with expertise in the field of dermatology.

METHODS

A half-day dermatology clinical skills session was introduced in the University of Toronto preclerkship medical school during the dermatology week. Sessions were co-led by staff or resident dermatologists. Sessions were evaluated using student pre- and postclinical skills test scores, as well as experience questionnaires completed by both tutors and students.

RESULTS

The clinical skills session was well received by both students and tutors, with no cumulative score less than 4.34 on a 5-point Likert scale. The majority of students agreed or strongly agreed that the introduction of clinical skills in the early years of the curriculum facilitated learning consolidation (99.5%). Comparison of pre- and post-test scores showed that students' dermatology comprehension improved by an average of 12.1% following completion of the session. In questionnaire responses, students and nondermatology co-tutors emphasized the impact of having an expert in the field of dermatology co-lead the session.

CONCLUSIONS

Students valued early clinical skills exposure to dermatology and felt it enhanced their knowledge and abilities. This study demonstrates learning consolidation when dermatologic didactic teachings are paired with practical clinical skills sessions.

Optimistic honesty: understanding surgeon and patient perspectives on hopeful communication in pancreatic cancer care

BACKGROUND

Prognosis conversations between surgical oncologists and patients with pancreatic cancer are critically important and challenging. Surgeons and their patients often have discrepant understandings of prognosis despite extensive conversations. Little is known about how surgeons approach prognosis conversations with these patients; patients' experiences with these conversations are also not well understood. This qualitative study sought to better understand surgeon and patient perspectives on communication in pancreatic cancer care with a view toward improvement.

METHODS

Grounded theory methodology was used. Semi-structured interviews were conducted with surgical oncologists and patients who had undergone surgical resection with curative intent for periampullary cancer. Data were collected and analyzed inductively and iteratively to the point of theoretical saturation.

RESULTS

10 surgeons and 10 patients participated. Three inter-linking concepts were found to drive surgeon-patient conversations: understanding, trust and hope. Surgeons delicately and purposefully tailored information for patients, striving to deliver essential though honest, empathetic and hopeful messages. Patients desired simple, truthful explanations that demonstrated caring and fostered optimism.

CONCLUSION

Surgeons and patients with pancreatic cancer value optimistic honesty in tailored prognosis conversations. Perceived discrepancies in surgeon-patient understanding must be contextualized within efforts to establish a sufficient understanding, high level of trust, and optimistic stance of hope.

Management of scalp psoriasis: current perspectives

Psoriasis is a chronic inflammatory condition. The age of onset, chronicity, physical, and psychosocial consequences of the disease cause psoriasis to have a significant impact on patient quality of life. Scalp psoriasis is no different, and effective treatment results in an improvement in quality of life. Successful management of scalp psoriasis includes topical therapies that are acceptable to the patient for mild-to-moderate disease, and systemic therapies for recalcitrant or moderate-to-severe disease. The most effective topical therapies are corticosteroid products, or combination products with calcipotriol and corticosteroid. Newer vehicle options provide more attractive and pleasing products for patients and may improve adherence. The current perspectives for management of scalp psoriasis are discussed including available data for systemic therapy of severe disease.

Dupilumab, A Monoclonal Antibody for Atopic Dermatitis: A Review of Current Literature

Atopic dermatitis results when aberrant barrier function and immune activation occur within the skin. Standard therapies for atopic dermatitis have fallen short, prompting efforts to discover novel therapeutics for this disease. Of these, dupilumab, a fully human monoclonal antibody that inhibits the actions of both IL-4 and IL-13, has shown the greatest promise. Clinical trials of systemic dupilumab in moderate-to-severe atopic dermatitis have demonstrated marked improvement in patient symptoms, including pruritus and clinically visible disease. Importantly, dupilumab treatment has been correlated with changes in the molecular signature of diseased skin, with reduction of both inflammatory and proliferative markers. Dupilumab recently received US FDA breakthrough therapy designation for atopic dermatitis, with ongoing trials in both adult and pediatric populations. Altogether, dupilumab has shed new light on the pathomechanisms driving atopic dermatitis and is making unprecedented advances towards highly effective control of this debilitating disease.

FGF23: mediator of poor prognosis in a sizeable subgroup of patients with castration-resistant prostate cancer presenting with severe hypophosphatemia?

Castration-resistant prostate cancer (CRPC) is an advanced and incurable stage of the second most frequently diagnosed malignancy in men globally. Current treatment options improve survival modestly but eventually fail due to intrinsic or acquired therapeutic resistance. A hypothesis is presented wherein circulating levels of fibroblast growth factor 23 (FGF23), an endocrine member of the fibroblast growth factor family with phosphaturic properties, are proposed as a prognostic and predictive marker to identify CRPC patients with poor prognosis that are amenable to FGF23 antibody therapy (FGF23i) or treatment with fibroblast growth factor receptor inhibitors (FGFRi). With respect to the latter, FGF23 may also serve as a pharmacodynamic marker enabling individualized FGFRi dosing. We recently discovered that the development of severe and sustained hypophosphatemia in CRPC patients undergoing zoledronic acid therapy for bone metastases was associated with markedly worse prognosis compared to patients without or with only mild and transient hypophosphatemia. Severe hypophosphatemia is a typical manifestation of tumor-induced hypophosphatemic osteomalacia (TIO), a paraneoplastic condition mediated by FGF23 overexpression in most instances. While the postulated tumor-promoting role of FGF23 in CRPC or other malignancies has not yet been studied, several lines of evidence suggest that FGF23 may mediate both severe hypophosphatemia (via its endocrine properties) and aggressive CRPC behavior (via autocrine and paracrine activities): (i) FGF23 and the necessary signalling machinery (i.e. members of the fibroblast growth factor receptor [FGFR] family and the essential co-receptor α-KLOTHO [KL]) are highly expressed in a sizeable subgroup of CRPC patients; (ii) FGF/FGFR signalling plays important roles in prostate cancer; (iii) FGF23 can induce its own expression via a positive autocrine feedback loop involving FGFR1; and (iv) this positive feedback loop may be triggered by bone-targeted therapies frequently used for the treatment of CRPC-associated bone metastases. While there is a lack of personalized treatment strategies in the management of CRPC to date, FGF23 targeted therapy has the potential to fill this unmet clinical need in the not-so-distant future. In fact, FGFRi are currently in advanced clinical testing for a number of malignancies such as kidney and lung cancer, but there is a lack of conclusive data on FGFRi therapy in patients selected for FGF/FGFR pathway activation.

Context-dependent role of ATG4B as target for autophagy inhibition in prostate cancer therapy

ATG4B belongs to the autophagin family of cysteine proteases required for autophagy, an emerging target of cancer therapy. Developing pharmacological ATG4B inhibitors is a very active area of research. However, detailed studies on the role of ATG4B during anticancer therapy are lacking. By analyzing PC-3 and C4-2 prostate cancer cells overexpressing dominant negative ATG4B(C74A)in vitro and in vivo, we show that the effects of ATG4B(C74A) are cell type, treatment, and context-dependent. ATG4B(C74A) expression can either amplify the effects of cytotoxic therapies or contribute to treatment resistance. Thus, the successful clinical application of ATG4B inhibitors will depend on finding predictive markers of response.

A comprehensive platform for highly multiplexed mammalian functional genetic screens

Background

Genome-wide screening in human and mouse cells using RNA interference and open reading frame over-expression libraries is rapidly becoming a viable experimental approach for many research labs. There are a variety of gene expression modulation libraries commercially available, however, detailed and validated protocols as well as the reagents necessary for deconvolving genome-scale gene screens using these libraries are lacking. As a solution, we designed a comprehensive platform for highly multiplexed functional genetic screens in human, mouse and yeast cells using popular, commercially available gene modulation libraries. The Gene Modulation Array Platform (GMAP) is a single microarray-based detection solution for deconvolution of loss and gain-of-function pooled screens.

Results

Experiments with specially constructed lentiviral-based plasmid pools containing ~78,000 shRNAs demonstrated that the GMAP is capable of deconvolving genome-wide shRNA "dropout" screens. Further experiments with a larger, ~90,000 shRNA pool demonstrate that equivalent results are obtained from plasmid pools and from genomic DNA derived from lentivirus infected cells. Parallel testing of large shRNA pools using GMAP and next-generation sequencing methods revealed that the two methods provide valid and complementary approaches to deconvolution of genome-wide shRNA screens. Additional experiments demonstrated that GMAP is equivalent to similar microarray-based products when used for deconvolution of open reading frame over-expression screens.

Conclusion

Herein, we demonstrate four major applications for the GMAP resource, including deconvolution of pooled RNAi screens in cells with at least 90,000 distinct shRNAs. We also provide detailed methodologies for pooled shRNA screen readout using GMAP and compare next-generation sequencing to GMAP (i.e. microarray) based deconvolution methods.

Pooled lentiviral shRNA screening for functional genomics in mammalian cells

Genome sequencing efforts have reformed the nature of biological inquiry, prompting the development of technologies for the functional annotation of mammalian genes. Based on methodologies originally discovered in plants and Caenorhabditis elegans, RNA interference has offered cell biologists an effective and reproducible approach to perturb gene function in mammalian cells and whole organisms. Initial application of RNA interference libraries targeting the human and mouse genomes relied on arrayed screening approaches, whereby each unique RNA interference reagent is arrayed into individual wells of a microtiter plate. These screens are not trivial to perform, requiring a substantial investment in infrastructure. In the past decade, many technological advances have been made that make genome-wide RNA interference screening more accessible to researchers and more feasible to perform in nonspecialized laboratories. Here, we describe a comprehensive protocol for pooled short-hairpin RNA screening, including methodologies for pooled lentivirus production, cell infection, genome-wide negative selection screening and resources for pooled screen deconvolution, and data analysis. As a technique, pooled shRNA screening is still in its infancy, but the methodology has already been successfully applied to probe diverse signaling pathways, as a means of drug target identification, and to identify essential genes in normal and cancer cell lines.

Abstract 12: Metastatic neuroblastoma cancer stem cells display a mixed phenotype of tumor and niche origin required for survival

Neuroblastoma (NB) is a pediatric tumor of neural crest origin, and is the most common cancer of infancy. 50% of patients have metastases at diagnosis, of which 85% will die after multiple relapses from metastatic disease. We identified tumor-initiating cells (TICs) from bone marrow (BM) metastases of high-risk patients that are propagated as spheres and that have many properties of cancer stem cells, and form NB in mice with as few as 1 cell. To understand patient relapse and disease progression, we compared NB-TICs from BM with those from tumor and brain metastases and SKPs, a normal pediatric stem cell counterpart, by cDNA microarray, flow cytometry, and whole genome shotgun sequencing transcriptome analysis. BM-derived NB-TICs expressed primitive neural crest and neuronal markers as well as hematopoietic markers from primitive, myeloid, and B-cell lineages and contained VDJ gene rearrangements, which are normally associated with B-cell leukemias. Hematopoietic genes were not expressed or expressed at very low levels in tumor-derived sphere lines and a line from an NB brain metastasis, however brain metastasis-derived TICs expressed CD133, while BM-derived NB-TICs did not. Furthermore, we found that shRNA to CD74, which is upregulated in B-cell lymphoma and multiple myeloma and is a therapeutic target for those cancers, induced the rapid death of NB-TICs but not normal SKPs. Interestingly cells co-staining for the hematopoietic markers CD45 or CD74 and the neural neural progenitor marker nestin were found in BM smears of patients with relapsed NB in the bone marrow.

We suggest that metastatic TICs from some tumors adopt resident niche-specific gene expression signatures, which may aid diagnosis and the development of novel treatments. We hypothesize that drugs used for leukemia may be efficacious therapeutics for metastatic NB, and are currently testing this hypothesis in mouse models.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 12.

A lentiviral functional proteomics approach identifies chromatin remodeling complexes important for the induction of pluripotency

Protein complexes and protein-protein interactions are essential for almost all cellular processes. Here, we establish a mammalian affinity purification and lentiviral expression (MAPLE) system for characterizing the subunit compositions of protein complexes. The system is flexible (i.e. multiple N- and C-terminal tags and multiple promoters), is compatible with Gateway cloning, and incorporates a reference peptide. Its major advantage is that it permits efficient and stable delivery of affinity-tagged open reading frames into most mammalian cell types. We benchmarked MAPLE with a number of human protein complexes involved in transcription, including the RNA polymerase II-associated factor, negative elongation factor, positive transcription elongation factor b, SWI/SNF, and mixed lineage leukemia complexes. In addition, MAPLE was used to identify an interaction between the reprogramming factor Klf4 and the Swi/Snf chromatin remodeling complex in mouse embryonic stem cells. We show that the SWI/SNF catalytic subunit Smarca2/Brm is up-regulated during the process of induced pluripotency and demonstrate a role for the catalytic subunits of the SWI/SNF complex during somatic cell reprogramming. Our data suggest that the transcription factor Klf4 facilitates chromatin remodeling during reprogramming.

Treatment of early seropositive rheumatoid arthritis with minocycline: four-year followup of a double-blind, placebo-controlled trial

OBJECTIVE

Rheumatoid arthritis (RA) causes substantial morbidity and mortality, and current treatments are suboptimal. Recent studies have demonstrated the short-term efficacy of minocycline in the treatment of patients with early RA. This study was undertaken to compare patients treated with conventional therapy in the early phase of their RA and those treated with minocycline, after 4 years of followup.

METHODS

Forty-six patients with seropositive RA of <1 year's duration had been enrolled in a double-blind study of minocycline (100 mg twice daily) versus placebo. After the blinded portion of the study (3-6 months, depending upon response), all patients were treated with conventional therapy. This report compares those patients randomized to receive placebo for 3 months and then conventional therapy for the duration of 4 years versus those originally randomized to receive minocycline.

RESULTS

Twenty of the 23 original minocycline-treated patients and 18 of the 23 original placebo-treated patients were available for followup (mean 4 years). At followup, RA was in remission (American College of Rheumatology criteria) without disease-modifying antirheumatic drug (DMARD) or steroid therapy in 8 of the patients originally treated with minocycline compared with 1 patient in the placebo group (P = 0.02). Ten patients in the minocycline group versus 16 in the original placebo group currently require DMARD therapy (P = 0.02).

CONCLUSION

Among patients with seropositive RA, remissions are more frequent and the need for DMARD therapy is less in those treated early in the disease course with minocycline compared with those treated with conventional therapy delayed by an average of only 3 months. Minocycline appears to be an effective therapy for early RA; further investigation into its mechanism of action is needed.

Treatment of early rheumatoid arthritis with minocycline or placebo: results of a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To determine if minocycline is an effective therapy for seropositive rheumatoid arthritis (RA) when used within the first year of disease.

METHODS

The Rheumatoid Arthritis Investigational Network enrolled 46 patients with RA of <1 year duration into a 6-month study of minocycline (100 mg twice daily) versus placebo. All patients were rheumatoid factor positive. The primary end point of the study was successful completion of 6 months of treatment with no drug toxicity while maintaining 50% improvement in composite symptoms of arthritis.

RESULTS

Eighteen of the 46 patients who were enrolled met 50% improvement criteria at 3 months, and maintained at least a 50% improvement for 6 months with no significant drug toxicity. Among them were 15 of the 23 patients (65%) treated with minocycline and 3 of 23 patients (13%) treated with placebo (P < 0.001).

CONCLUSION

In patients with early seropositive RA, therapy with minocycline is superior to placebo.