Spatially mapping the immune landscape of melanoma using imaging mass cytometry.

Melanoma is an immunogenic cancer with a high response rate to immune checkpoint inhibitors (ICIs). It harbors a high mutation burden compared with other cancers and, as a result, has abundant tumor-infiltrating lymphocytes (TILs) within its microenvironment. However, understanding the complex interplay between the stroma, tumor cells, and distinct TIL subsets remains a substantial challenge in immune oncology. To properly study this interplay, quantifying spatial relationships of multiple cell types within the tumor microenvironment is crucial. To address this, we used cytometry time-of-flight (CyTOF) imaging mass cytometry (IMC) to simultaneously quantify the expression of 35 protein markers, characterizing the microenvironment of 5 benign nevi and 67 melanomas. We profiled more than 220,000 individual cells to identify melanoma, lymphocyte subsets, macrophage/monocyte, and stromal cell populations, allowing for in-depth spatial quantification of the melanoma microenvironment. We found that within pretreatment melanomas, the abundance of proliferating antigen-experienced cytotoxic T cells (CD8+CD45RO+Ki67+) and the proximity of antigen-experienced cytotoxic T cells to melanoma cells were associated with positive response to ICIs. Our study highlights the potential of multiplexed single-cell technology to quantify spatial cell-cell interactions within the tumor microenvironment to understand immune therapy responses.

Multimeric Anti-DR5 IgM Agonist Antibody IGM-8444 Is a Potent Inducer of Cancer Cell Apoptosis and Synergizes with Chemotherapy and BCL-2 Inhibitor ABT-199.

Death receptor 5 (DR5) is an attractive target for cancer therapy due to its broad upregulated expression in multiple cancers and ability to directly induce apoptosis. Though anti-DR5 IgG antibodies have been evaluated in clinical trials, limited efficacy has been attributed to insufficient receptor crosslinking. IGM-8444 is an engineered, multivalent agonistic IgM antibody with 10 binding sites to DR5 that induces cancer cell apoptosis through efficient DR5 multimerization. IGM-8444 bound to DR5 with high avidity and was substantially more potent than an IgG with the same binding domains. IGM-8444 induced cytotoxicity in a broad panel of solid and hematologic cancer cell lines but did not kill primary human hepatocytes in vitro, a potential toxicity of DR5 agonists. In multiple xenograft tumor models, IGM-8444 monotherapy inhibited tumor growth, with strong and sustained tumor regression observed in a gastric PDX model. When combined with chemotherapy or the BCL-2 inhibitor ABT-199, IGM-8444 exhibited synergistic in vitro tumor cytotoxicity and enhanced in vivo efficacy, without augmenting in vitro hepatotoxicity. These results support the clinical development of IGM-8444 in solid and hematologic malignancies as a monotherapy and in combination with chemotherapy or BCL-2 inhibition.

Short and long-term barriers and facilitators of skin self-examination among individuals diagnosed with melanoma.

BACKGROUND: Melanoma can be lethal if not detected early and treated. Early detection can be facilitated via skin self-examination (SSE) and as such, SSE is part of melanoma follow-up care for individuals with a prior history, who face a life-long risk of reoccurrence. The objective of the current study was to identify short- and long-term predictors of SSE among melanoma survivors to inform future prevention interventions in high-risk groups. METHOD: This is an observational study with longitudinal assessments conducted with adult melanoma patients in active follow-up care. PRIMARY OUTCOME MEASURES: Behavioral outcomes, comprehensive SSE (checking up to 5 body areas in the last 3 months) and optimal SSE (checking the entire body at least monthly in the last 3 months) were assessed at 3, 12, and 24 months post a dermatological educational session on skin cancer prevention. T tests and chi square analyses were used to examine changes in outcomes from 3 to 12 and 24 months. Linear and logistic regression models were used to examine the association between predictors and the primary outcomes. RESULTS: Comprehensive SSE did not decrease significantly from 3 (M = 2.7, SD = 1.1) to 12 (M = 2.6, SD = 1.2) and 24 months (M = 2.4, SD = 1.2) post the education session, with the stronger predictor at all timepoints being intentions to perform SSE. Optimal SSE was higher at 3 months (59%) compared to 12 (46%) and 24 months (34%), with key predictors including self-efficacy and intentions to perform SSE and male sex at 3 months post; self-efficacy and reliance on medical advice at 12 months; and (lower) education and self-efficacy at 24 months. CONCLUSIONS: The key findings of this study are that 1) survivors maintain SSE behaviour over time, but rates of SSE performed in agreement with medical recommendations are higher immediately post standard dermatological education (i.e. usual care) and decrease somewhat over a 24-month period; and 2) the strongest psycho-social predictors of SSE are intentions and self-efficacy to perform the behavior, which are highly modifiable, for example via motivational interviewing and goal setting health interventions.

Composite Cutaneous Lymphoma (Iatrogenic Immunodeficiency-Associated Lymphoproliferative Disorder) in a Patient with Rheumatoid Arthritis Treated with Methotrexate: Staging and Evaluation of Response to Therapy with 18F-FDG PET/CT.

A 67 year old woman with a 10 year history of rheumatoid arthritis (RA) treated with methotrexate and prednisone, presented with a 2 year history of worsening multiple cutaneous plaques of variable appearance. Two distinct skin lesions were biopsied to reveal a composite cutaneous lymphoma, possibly caused by long term methotrexate therapy. An [18F] fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) was performed to stage the malignancy, and was later repeated to evaluate response to chemotherapy, which guided subsequent management. We present the PET/CT imaging findings of this very rare iatrogenic (methotrexate induced) immunodeficiency-associated lymphoproliferative disorder.

Prospective Case Series of Cutaneous Adverse Effects Associated With Dabrafenib and Trametinib.

BACKGROUND: Dabrafenib, a novel selective small-molecule inhibitor of BRAF, has been shown to increase overall survival in patients with unresectable metastatic melanoma harboring the BRAF V600E mutation. The development of resistance has led to combination therapy with selective MEK inhibitor trametinib. Compared with vemurafenib, dabrafenib is a more recent BRAF inhibitor approved by the Food and Drug Administration in May 2013 for metastatic melanoma; fewer data are available in the current literature regarding cutaneous toxicity. OBJECTIVES: We sought to present additional cutaneous side effects of dabrafenib and trametinib and follow their evolution and management. METHODS: We carried out a prospective study of 14 patients treated with dabrafenib alone or with trametinib. Patients were followed every 4 weeks, and we collected detailed cutaneous symptoms, photos, and biopsy specimens. RESULTS: All patients presented with at least 1 adverse skin reaction. The mean duration of treatment was 24 weeks. The most common adverse effect was papillomas (7/14), followed by palmoplantar hyperkeratosis (5/14), alopecia (5/14), and seborrheic dermatitis-like eruption (2/14). Three patients who received trametinib developed an acneiform eruption (3/5). One patient developed a keratoacanthoma-like squamous cell carcinoma. Side effects presented as early as 2 weeks after starting therapy, with a mean time of onset of 9 weeks. CONCLUSION: Selective BRAF inhibitor dabrafenib and MEK inhibitor trametinib are associated with multiple skin adverse effects. Given their recent approval and the potential for malignant lesions to develop on treatment, awareness of potential adverse effects and their management is necessary.

Predictors of skin self-examination before and after a melanoma diagnosis: the role of medical advice and patient's level of education.

BACKGROUND: Cutaneous melanoma is the fastest growing tumor of the skin and the median life span of patients with advanced disease is less than a year. Melanoma-related mortality can be reduced through early detection via clinical skin exams and patient self-examination. Despite the potential to reducing the medical burden associated with clinical skin exams, systematic and regular skin self-examinations (SSE) are rarely performed. The current study examined psychosocial predictors of SSE and changes in SSE behavior from pre- to post-diagnosis in order to guide future melanoma prevention initiatives. FINDINGS: A consecutive sample of 47 melanoma survivors was drawn from a tertiary care clinic. Most melanomas had been detected by patients, spouses and other laypersons. Higher education was related to more frequent SSE at pre-diagnosis, more thorough SSE at post-diagnosis, and more frequent reports of having been advised to perform SSE at post-diagnosis. SSE behaviors increased significantly from pre- to post-diagnosis. CONCLUSIONS: These findings suggest that different patient subgroups display varied knowledge base, readiness for change, and receptiveness for medical advice. Thus, interventions seeking to enhance skin self-exam practice may be most effective when the individual's psychosocial characteristics are taken into account.

Barriers and facilitators of adherence to medical advice on skin self-examination during melanoma follow-up care.

BACKGROUND: Melanoma is the fastest growing tumor of the skin, which disproportionately affects younger and middle-aged adults. As melanomas are visible, recognizable, and highly curable while in early stages, early diagnosis is one of the most effective measures to decrease melanoma-related mortality. Skin self-examination results in earlier detection and removal of the melanoma. Due to the elevated risk of survivors for developing subsequent melanomas, monthly self-exams are strongly recommended as part of follow-up care. Yet, only a minority of high-risk individuals practices systematic and regular self-exams. This can be improved through patient education. However, dermatological education is effective only in about 50% of the cases and little is known about those who do not respond. In the current literature, psychosocial variables like distress, coping with cancer, as well as partner and physician support are widely neglected in relation to the practice of skin self-examination, despite the fact that they have been shown to be essential for other health behaviors and for adherence to medical advice. Moreover, the current body of knowledge is compromised by the inconsistent conceptualization of SSE. The main objective of the current project is to examine psychosocial predictors of skin self-examination using on a rigorous and clinically sound methodology. METHODS/DESIGN: The longitudinal, mixed-method study examines key psychosocial variables related to the acquisition and to the long-term maintenance of skin self-examination in 200 patients with melanoma. Practice of self-exam behaviors is assessed at 3 and 12 months after receiving an educational intervention designed based on best-practice standards. Examined predictors of skin self-exam behaviors include biological sex, perceived self-exam efficacy, distress, partner and physician support, and coping strategies. Qualitative analyses of semi-structured interviews will complement and enlighten the quantitative findings. DISCUSSION: The identification of short and long-term predictors of skin self-examination and an increased understanding of barriers will allow health care professionals to better address patient difficulties in adhering to this life-saving health behavior. Furthermore, the findings will enable the development and evaluation of evidence-based, comprehensive intervention strategies. Ultimately, these findings could impact a wide range of outreach programs and secondary prevention initiatives for other populations with increased melanoma risk.

Chemical genetic screen for AMPKα2 substrates uncovers a network of proteins involved in mitosis.

The energy-sensing AMP-activated protein kinase (AMPK) is activated by low nutrient levels. Functions of AMPK, other than its role in cellular metabolism, are just beginning to emerge. Here we use a chemical genetics screen to identify direct substrates of AMPK in human cells. We find that AMPK phosphorylates 28 previously unidentified substrates, several of which are involved in mitosis and cytokinesis. We identify the residues phosphorylated by AMPK in vivo in several substrates, including protein phosphatase 1 regulatory subunit 12C (PPP1R12C) and p21-activated protein kinase (PAK2). AMPK-induced phosphorylation is necessary for PPP1R12C interaction with 14-3-3 and phosphorylation of myosin regulatory light chain. Both AMPK activity and PPP1R12C phosphorylation are increased in mitotic cells and are important for mitosis completion. These findings suggest that AMPK coordinates nutrient status with mitosis completion, which may be critical for the organism's response to low nutrients during development, or in adult stem and cancer cells.

The mammalian target of rapamycin regulates cholesterol biosynthetic gene expression and exhibits a rapamycin-resistant transcriptional profile.

The mammalian target of rapamycin (mTOR) is a central regulator of cell growth and proliferation in response to growth factor and nutrient signaling. Consequently, this kinase is implicated in metabolic diseases including cancer and diabetes, so there is great interest in understanding the complete spectrum of mTOR-regulated networks. mTOR exists in two functionally distinct complexes, mTORC1 and mTORC2, and whereas the natural product rapamycin inhibits only a subset of mTORC1 functions, recently developed ATP-competitive mTOR inhibitors have revealed new roles for both complexes. A number of studies have highlighted mTORC1 as a regulator of lipid homeostasis. We show that the ATP-competitive inhibitor PP242, but not rapamycin, significantly down-regulates cholesterol biosynthesis genes in a 4E-BP1-dependent manner in NIH 3T3 cells, whereas S6 kinase 1 is the dominant regulator in hepatocellular carcinoma cells. To identify other rapamycin-resistant transcriptional outputs of mTOR, we compared the expression profiles of NIH 3T3 cells treated with rapamycin versus PP242. PP242 caused 1,666 genes to be differentially expressed whereas rapamycin affected only 88 genes. Our analysis provides a genomewide view of the transcriptional outputs of mTOR signaling that are insensitive to rapamycin.

Evidence and considerations in the application of chemical peels in skin disorders and aesthetic resurfacing.

Chemical peeling is a popular, relatively inexpensive, and generally safe method for treatment of some skin disorders and to refresh and rejuvenate skin. This article focuses on chemical peels and their use in routine clinical practice. Chemical peels are classified by the depth of action into superficial, medium, and deep peels. The depth of the peel is correlated with clinical changes, with the greatest change achieved by deep peels. However, the depth is also associated with longer healing times and the potential for complications. A wide variety of peels are available, utilizing various topical agents and concentrations, including a recent salicylic acid derivative, beta-lipohydroxy acid, which has properties that may expand the clinical use of peels. Superficial peels, penetrating only the epidermis, can be used to enhance treatment for a variety of conditions, including acne, melasma, dyschromias, photodamage, and actinic keratoses. Medium-depth peels, penetrating to the papillary dermis, may be used for dyschromia, multiple solar keratoses, superficial scars, and pigmentary disorders. Deep peels, affecting reticular dermis, may be used for severe photoaging, deep wrinkles, or scars. Peels can be combined with other in-office facial resurfacing techniques to optimize outcomes and enhance patient satisfaction and allow clinicians to tailor the treatment to individual patient needs. Successful outcomes are based on a careful patient selection as well as appropriate use of specific peeling agents. Used properly, the chemical peel has the potential to fill an important therapeutic need in the dermatologist's and plastic surgeon's armamentarium.

Composite cutaneous lymphoma in a patient with rheumatoid arthritis treated with methotrexate.

Patients with rheumatoid arthritis, whether treated or not with immunosuppressive agents including methotrexate, have an increased risk of lymphoproliferative disorders. Termed "iatrogenic immunodeficiency-associated lymphoproliferative disorders" in the 2008 World Health Organization classification of lymphoid neoplasms, they include Hodgkin and non-Hodgkin lymphomas. Composite lymphomas are rare, particularly in skin, with none reported in immunodeficiency states. We report the case of a 67 year-old woman with a long history of rheumatoid arthritis, on methotrexate treatment, who developed multiple skin lesions exhibiting a malignant infiltrate displaying both B- and T-cell phenotypes and dual clonal gene rearrangement by polymerase chain reaction, consistent with a cutaneous composite lymphoma. The patient received chemotherapy including rituximab with partial response, but the T-cell component recurred. To the best of our knowledge, this is the first case report of a cutaneous composite lymphoma in a patient with an iatrogenic immunodeficiency representing a dual challenge, diagnostic for the pathologist and therapeutic for the hematologist.

Chemical genetic approach for kinase-substrate mapping by covalent capture of thiophosphopeptides and analysis by mass spectrometry.

Mapping kinase-substrate interactions demands robust methods to rapidly and unequivocally identify substrates from complex protein mixtures. Toward this goal, we present a method in which a kinase, engineered to utilize synthetic ATPγS analogs, specifically thiophosphorylates its substrates in a complex lysate. The thiophosphate label provides a bio-orthogonal tag that can be used to affinity purify and identify labeled proteins. Following the labeling reaction, proteins are digested with trypsin; thiol-containing peptides are then covalently captured and non-thiol-containing peptides are washed from the resin. Oxidation-promoted hydrolysis, at sites of thiophosphorylation, releases phosphopeptides for analysis by tandem mass spectrometry. By incorporating two specificity gates-kinase engineering and peptide affinity purification-this method yields high-confidence substrate identifications. This method gives both the identity of the substrates and phosphorylation-site localization. With this information, investigators can analyze the biological significance of the phosphorylation mark immediately following confirmation of the kinase-substrate relationship. Here, we provide an optimized version of this technique to further enable widespread utilization of this technology. Curr. Protoc. Chem Biol. 2:15-36. © 2010 by John Wiley & Sons, Inc.

Regulation of meiotic recombination via Mek1-mediated Rad54 phosphorylation.

A preference for homologs over sister chromatids in homologous recombination is a fundamental difference in meiotic versus mitotic cells. In budding yeast, the bias for interhomolog recombination in meiosis requires the Dmc1 recombinase and the meiosis-specific kinase Mek1, which suppresses engagement of sister chromatids by the mitotic recombinase Rad51. Here, a combination of proteomic, biochemical, and genetic approaches has identified an additional role for Mek1 in inhibiting the activity of the Rad51 recombinase through phosphorylation of its binding partner, Rad54. Rad54 phosphorylation of threonine 132 attenuates complex formation with Rad51, and a negative charge at this position reduces Rad51 function in vitro and in vivo. Thus, Mek1 phosphorylation provides a dynamic means of controlling recombination partner choice in meiosis in two ways: (1) it reduces Rad51 activity through inhibition of Rad51/Rad54 complex formation, and (2) it suppresses Rad51-mediated strand invasion of sister chromatids via a Rad54-independent mechanism.

Clinical role and application of superficial chemical peels in today's practice.

Chemical peeling is a popular, relatively inexpensive, and generally safe method to refresh and rejuvenate skin. This review focuses on superficial chemical peels and their use in routine clinical practice. A wide variety of peels are available, utilizing various actives and concentrations, including a recently introduced salicylic acid derivative, beta-lipohydroxy acid, which has properties that may expand the clinical use of peels. Superficial peels can be used to enhance treatment within a variety of conditions, including acne, melasma, dyschromias, photodamage and actinic keratoses. In addition, peels can be combined with other in-office procedures to optimize outcomes and enhance patient satisfaction, and allow clinicians to tailor the treatment to individual patient's needs. Successful outcomes are based on a thorough understanding and application of correct chemical peel procedures, including history-taking, pretreatment, preparation, peel selection, patient communication and maintenance regimens.Used properly, the superficial chemical peel has the potential to fill an important therapeutic need in the treatment armamentarium of dermatologists and plastic surgeons.

Short-contact clobetasol propionate shampoo 0.05% improves quality of life in patients with scalp psoriasis.

Scalp psoriasis has a considerable impact on the quality of life (QOL) of patients, and most patients are dissatisfied with available treatments. Clobetasol propionate shampoo 0.05% has been shown to be effective and safe for moderate to severe scalp psoriasis. We evaluated the effect of clobetasol propionate shampoo on QOL and the degree of participant satisfaction with the product. Participants received once-daily treatment for up to 4 weeks. Their QOL and degree of satisfaction were evaluated by questionnaires. The mean (standard deviation) Dermatology Life Quality Index (DLQI) score decreased significantly from 7.0 (4.9) at baseline to 3.2 (3.2) at week 4 (P<.001). Participants who considered the disease as having a small effect or no effect on their QOL increased from 45.6% at baseline to 81.7% at week 4. Most participants were satisfied with the cosmetic acceptability and the efficacy and safety aspects of the product, considered it better than prior treatments, and would use it again in the future. Therefore, we conclude that treatment with clobetasol propionate shampoo improved the QOL of participants and resulted in high satisfaction.

Effects of ginseng saponins on beta-amyloid-induced amnesia in rats.

We have previously demonstrated that ginseng saponins (GS) can reverse the inhibitory effect of beta-amyloid on acetylcholine (ACh) release in the hippocampal slices. The present study was carried out to examine whether GS has any beneficial effects against amnesia induced by beta-amyloid peptides in vivo. Intracerebroventricular injection of 50 microg, but not 10 microg, beta-amyloid fragment(25-35) markedly impaired the performance of rats in avoiding a shock prod, confirming the amnesiac effect of beta-amyloid. Chronically treating the rats with GS (orally, 5 days before icv beta-amyloid injection and 7 days afterward) resulted in a dose-related improvement against beta-amyloid-induced amnesia; a significant reversion was observed at the highest GS dose (80 mg/kg/day). Post-treatment analysis on K(+)-evoked [(3)H]-ACh release from the hippocampal slices showed that beta-amyloid-treatment significantly reduced ACh release from that of the control group. However, pre-treatment with GS completely protected the animal against beta-amyloid-induced reduction of hippocampal ACh release. In contrast, treating the animals with the same optimal dose of GS and duration but only after icv beta-amyloid injection was found to be ineffective in obliterating beta-amyloid's amnesiac effect. Taken together, these observations indicated that GS pre-treatment can functionally prevent the beta-amyloid-induced memory loss possibly by minimizing the inhibitory effect of beta-amyloid on hippocampal cholinergic transmission.

Dermatologic surgery practice and skin cancer treatment in Canada: results of a national survey.

BACKGROUND: Although traditionally considered a medical subspecialty, dermatology has rapidly evolved over the past two decades to encompass a wide variety of cutaneous surgical procedures. OBJECTIVE: The study was carried out to evaluate the status of dermatologic surgery practice and skin cancer treatment in Canada. METHODS: In 2003, 550 practicing Canadian dermatologists were surveyed. RESULTS: Two hundred fifty-one dermatologists responded to the questionnaire, with the majority practicing in an urban part-time academic, part-time private setting. Statistics are presented on the types and demographics of dermatosurgical and cosmetic procedures performed, as well as on the specific dermatosurgical therapies used in the treatment of various cutaneous malignancies. CONCLUSIONS: The survey provides a current picture of dermatologic surgery practice and skin cancer treatment in Canada. The data suggest that Canadian dermatologists are further embracing surgical and cosmetic procedures.

Impact of melanoma diagnosis on sun-awareness and protection: efficacy of education campaigns in a high-risk population.

BACKGROUND: Malignant melanoma is a significant cause of morbidity and mortality worldwide. Sun-awareness campaigns increase public knowledge but may not translate into behavioral changes in practice, which is particularly alarming when reported for individuals in high-risk groups. In particular, patients diagnosed with melanoma are at increased risk of developing subsequent primary melanomas compared with the general population. OBJECTIVES: The study was undertaken (1) to assess whether patients with known risk factors for developing melanoma had been exposed to preventative campaign messages prior to their diagnosis, (2) to quantify whether the diagnosis of melanoma changed sun-related attitudes and behavior, and (3) to assess the adequacy of sun-related advice given to patients with melanoma, as well as their compliance with the advice. METHODS: Using an anonymous questionnaire, 217 patients previously diagnosed with melanoma were interviewed on the source and frequency of received sun-related advice, as well as on their knowledge, attitudes, and behavior toward sun protection before and after the diagnosis. RESULTS: The number of patients who reported receiving sun-related advice after being diagnosed with melanoma increased by 36% (52% pre-vs. 88% postDiagnosis), with advice being given more frequently and more often by a physician (19% pre- vs. 49% postdiagnosis). Furthermore, sun-related attitudes and behavioral practices were positively altered. Yet, patients with known risk factors were not preferentially targeted for advice before their diagnosis. CONCLUSIONS: The diagnosis of melanoma leads to increased sun-awareness and protection. While dermatologists should continue their efforts to promote and reinforce sun-awareness in patients with melanoma, additional emphasis on preventative targeting of high-risk individuals would be of marked benefit in decreasing the overall incidence of melanoma. Non-dermatologists, such as family physicians, can be key players in this preventative campaign, and can be educated to recognize and educate patients at risk, as well as direct them to be followed under dermatology care.