Targeting histone deacetylase 6 mediates a dual anti-melanoma effect: Enhanced antitumor immunity and impaired cell proliferation

The median survival for metastatic melanoma is in the realm of 8-16 months and there are few therapies that offer significant improvement in overall survival. One of the recent advances in cancer treatment focuses on epigenetic modifiers to alter the survivability and immunogenicity of cancer cells. Our group and others have previously demonstrated that pan-HDAC inhibitors induce apoptosis, cell cycle arrest and changes in the immunogenicity of melanoma cells. Here we interrogated specific HDACs which may be responsible for this effect. We found that both genetic abrogation and pharmacologic inhibition of HDAC6 decreases in vitro proliferation and induces G1 arrest of melanoma cell lines without inducing apoptosis. Moreover, targeting this molecule led to an important upregulation in the expression of tumor associated antigens and MHC class I, suggesting a potential improvement in the immunogenicity of these cells. Of note, this anti-melanoma activity was operative regardless of mutational status of the cells. These effects translated into a pronounced delay of in vivo melanoma tumor growth which was, at least in part, dependent on intact immunity as evidenced by the restoration of tumor growth after CD4+ and CD8+ depletion. Given our findings, we provide the initial rationale for the further development of selective HDAC6 inhibitors as potential therapeutic anti-melanoma agents.

Characteristics of pyrexia in BRAFV600E/K metastatic melanoma patients treated with combined dabrafenib and trametinib in a phase I/II clinical trial

BACKGROUND

Pyrexia is a frequent adverse event with combined dabrafenib and trametinib therapy (CombiDT), but little is known of its clinical associations, etiology, or appropriate management.

PATIENTS AND METHODS

All patients on the BRF133220 phase I/II trial of CombiDT treated at the standard dose (150/2) were included for assessment of pyrexia (n = 201). BRAF and MEK inhibitor-naïve patients (n = 117) were included for efficacy analyses. Pyrexia was defined as temperature ≥38°C (≥100.4(°)F) or related symptoms.

RESULTS

Fifty-nine percent of patients developed pyrexia during treatment, 24% of which had pyrexia symptoms without a recorded elevation in body temperature. Pyrexia was grade 2+ in 60% of pyrexia patients. Median time to onset of first pyrexia was 19 days, with a median duration of 9 days. Pyrexia patients had a median of two pyrexia events, but 21% had three or more events. Various pyrexia management approaches were conducted in this study. A trend was observed between dabrafenib and hydroxy-dabrafenib exposure and pyrexia. No baseline clinical characteristics predicted pyrexia, and pyrexia was not statistically significantly associated with treatment outcome.

CONCLUSIONS

Pyrexia is a frequent and recurrent toxicity with CombiDT treatment. No baseline features predict pyrexia, and it is not associated with clinical outcome. Dabrafenib and metabolite exposure may contribute to the etiology of pyrexia. The optimal secondary prophylaxis for pyrexia is best studied in a prospective trial.

Big Data in Healthcare - Defining the Digital Persona through User Contexts from the Micro to the Macro. Contribution of the IMIA Organizational and Social Issues WG

OBJECTIVES

While big data offers enormous potential for improving healthcare delivery, many of the existing claims concerning big data in healthcare are based on anecdotal reports and theoretical vision papers, rather than scientific evidence based on empirical research. Historically, the implementation of health information technology has resulted in unintended consequences at the individual, organizational and social levels, but these unintended consequences of collecting data have remained unaddressed in the literature on big data. The objective of this paper is to provide insights into big data from the perspective of people, social and organizational considerations.

METHOD

We draw upon the concept of persona to define the digital persona as the intersection of data, tasks and context for different user groups. We then describe how the digital persona can serve as a framework to understanding sociotechnical considerations of big data implementation. We then discuss the digital persona in the context of micro, meso and macro user groups across the 3 Vs of big data.

RESULTS

We provide insights into the potential benefits and challenges of applying big data approaches to healthcare as well as how to position these approaches to achieve health system objectives such as patient safety or patient-engaged care delivery. We also provide a framework for defining the digital persona at a micro, meso and macro level to help understand the user contexts of big data solutions.

CONCLUSION

While big data provides great potential for improving healthcare delivery, it is essential that we consider the individual, social and organizational contexts of data use when implementing big data solutions.

Soluble immunoglobulin A in breast milk is inversely associated with atopic dermatitis at early age: the PASTURE cohort study

BACKGROUND

The role of breastfeeding for the development of atopic diseases in childhood is contradictory. This might be due to differences in the composition of breast milk and levels of antimicrobial and anti-inflammatory components.

OBJECTIVE

The objective of this study was to examine whether levels of total immunoglobulin A (IgA) or transforming growth factor-β1 (TGF-β1) in breast milk were associated with the risk of developing atopic dermatitis (AD), atopic sensitization or asthma at early age taking breastfeeding duration into account.

METHODS

The birth cohort study PASTURE conducted in Finland, France, Germany and Switzerland provided 610 breast milk samples collected 2 months after delivery in which soluble IgA (sIgA) and TGF-β1 levels were measured by ELISA. Duration of breastfeeding was assessed using weekly food frequency diaries from month 3 to month 12. Data on environmental factors, AD and asthma were collected by questionnaires from pregnancy up to age 6. Atopic status was defined by specific IgE levels in blood collected at the ages of 4 and 6 years. Multivariate logistic regression models were used for statistical analysis.

RESULTS

Soluble IgA and TGF-β1 levels in breast milk differed between countries, and sIgA levels were associated with environmental factors related to microbial load, for example, contact to farm animals or cats during pregnancy, but not with raw milk consumption. sIgA levels were inversely associated with AD up to the of age 2 years (P-value for adjusted linear trend: 0.005), independent of breastfeeding duration. The dose of sIgA ingested in the first year of life was associated with reduced risk of AD up to the age of 2 (aOR, 95% CI: 0.74; 0.55-0.99) and 4 years (0.73; 0.55-0.96). No clear associations between sIgA and atopy or asthma up to age 6 were observed. TGF-β1 showed no consistent association with any investigated health outcome.

CONCLUSION AND CLINICAL RELEVANCE

IgA in breast milk might protect against the development of AD.

Serum vitamin E concentrations at 1 year and risk of atopy, atopic dermatitis, wheezing, and asthma in childhood: the PASTURE study

BACKGROUND

Prospective studies investigating the role of serum vitamin E concentrations during early life in the development of childhood allergies and asthma are limited.

OBJECTIVE

To study the associations between serum vitamin E concentrations at first year of life and longitudinal development of atopy, atopic dermatitis, wheeze, and asthma up to 6 years of age.

METHODS

The setting was the PASTURE study, a multicenter prospective birth cohort study in five European rural settings. Children of 1133 mothers recruited during pregnancy were followed from birth with measurement of serum vitamin E levels at year 1 and repeated assessments of serum immunoglobulin E antibodies (year 1, 4.5, 6), atopic dermatitis, wheezing symptoms, and asthma (year 1, 1.5, 2, 3, 4, 5, 6).

RESULTS

At 6 years of age, 66% and 82% of the original 1133 subjects underwent blood test for IgE and answered the questionnaire, respectively. We did not observe any statistically significant associations between serum vitamin E concentrations at year 1 and the endpoints, but borderline inverse associations between alpha tocopherol and wheezing without cold (OR 0.45, 95% CI 0.19-1.09) and any wheezing symptom (OR 0.52, 95% CI 0.27-1.02).

CONCLUSIONS

Serum vitamin E concentrations at year 1 were not associated with allergies or asthma by 6 years of age. While further prospective studies with repeated assessments of vitamin E during early life may clarify its putative role in the development of the diseases, it is also possible that the antioxidant hypothesis in the development of allergies and asthma does not hold.

Abstract P4-01-19: Enhanced sensitivity to detect metastases of breast cancer to the lung and monitor response to inhibition of metastasis by IGF1R inhibitor using SWIFT MRI

Breast cancers metastasize to the bone, lung, brain and liver and mortality from breast cancer is due to metastases. Drugs that inhibit metastasis in particular of triple negative (TN) breast cancers, more sensitive methods to image metastases and imaging biomarkers to monitor response to these drugs at sites of metastasis are needed to reduce mortality. The type I insulin-like growth factor receptor (IGF1R) regulates metastasis and drugs targeting IGF1R and or insulin receptor inhibit metastasis of TN breast cancer cells in mouse models. The initial clinical trials of these drugs have not been very successful and point to the need to develop imaging biomarkers for this therapy. While MRI is a powerful tool for detecting and imaging cancer, its utility in imaging metastasis to the lung is limited due to the challenges of lung MRI with conventional 3D gradient echo (GRE). MRI does not visualize lung well, mainly due to the abundance of air-tissue interfaces, which cause the MR signal to decay too rapidly for conventional MRI pulse sequences to capture. Clinically lung metastases are monitored by CT or PET but exposure of patients to ionizing radiation is a concern and problematic in longitudinal studies monitoring response to a targeted drug. Further MRI can also be useful in measuring metabolite levels using MR spectroscopy (MRS). Therefore, we evaluated the capability of a novel MR sequence called sweep imaging with Fourier transformation (SWIFT), where the data is acquired concurrently with the radiofrequency pulse, to detect breast cancer metastases to lung and test if inhibition of metastases by an IGF1R targeted drug can be monitored by SWIFT. We used the tail vein injection model of breast cancer metastasis with MDA-MB-231-LM2, a lung-seeking metastatic TN breast cancer cell line. Lung metastases were monitored with bioluminescence imaging (BLI) and MRI every week. MRI was done with two pulse sequences: SWIFT (with a short echo time or TE∼3 μs) and GRE (with a longer TE = 2.2 ms). SWIFT showed significantly higher sensitivity in detecting signals from lung parenchyma compared to GRE and structural information was visible in the area of the lungs. Metastatic tumor growth in the lung induced a progressive increase in signal from the lung parenchyma in SWIFT images. MIP images from SWIFT clearly visualized the lung vascular structures and their disruption due to progression of breast cancer metastasis. To test if SWIFT can also be useful in monitoring inhibition of metastases, mice injected with cells were treated with either vehicle or an IGF1R inhibitor (huEM164) twice a week. When inhibition of metastases in the huEM164 treated group compared to the vehicle group was evident by BLI, MR images were acquired. SWIFT was sensitive in detecting the inhibition of metastases by the IGF1R antibody. Our data show that high sensitivity to fast-decaying signals and tolerance to the magnetic susceptibility in SWIFT enhance the capability to detect signal and structural changes in the lung parenchyma and vasculature due to metastasis of breast cancer. Further, SWIFT was also sensitive to monitor inhibition of metastasis in response to IGF1R targeted drugs.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-01-19.

Evoked pressure curves from the external anal sphincter following transcranial magnetic stimulation in healthy volunteers and patients with faecal incontinence

AIM

The hypothesis was tested that evoked pressure curves (EPCs) after transcranial magnetic stimulation (TMS) would provide additional neuropathophysiological information on the descending pathways to the external anal sphincter (EAS) in patients with faecal incontinence (FI).

METHOD

Twenty-five healthy subjects and 69 patients with FI were investigated. TMS was applied to the vertex, and EPCs were recorded with a probe placed through the EAS. TMS was performed with the EAS at rest and during contraction (facilitated responses). At least three responses were recorded for each modality. Clinical data and anorectal manometric, electrophysiological perineal and transanal ultrasound recordings were compared with respect to the EPC results.

RESULTS

There was no statistically significant difference between the EPCs of healthy subjects and FI patients. Twenty-three per cent of the FI patients had abnormal EPC latencies, with significantly lower voluntary contraction amplitudes (P = 0.03) and significantly higher rectal sensation (P = 0.04) than the other group. We found no significant difference between FI patients with and without abnormal EPC latencies in terms of clinical characteristics and electrophysiological and endoanal ultrasound parameters. There was no difference in the identified causes of the FI between the two groups.

CONCLUSION

As abnormal EPC latencies were found in 23% of FI patients with no known central neurological disease, abnormal EPC latencies might reveal undetected lesions of descending pathways in patients with FI.