IDEA Group Consensus Statement on Medical Management of Adult Gender Incongruent Individuals Seeking Gender Affirmation as Male

Gender-affirming hormone therapy (GAHT) is the most frequent treatment offered to gender-incongruent individuals, which reduces dysphoria. The goal of therapy among gender-incongruent individuals seeking gender affirmation as male is to change their secondary sex characteristics to affect masculine physical appearances. GAHT greatly improves mental health and quality of life among gender incongruent individuals. India-specific guideline for appropriate care for gender-incongruent individuals is almost absent. This document is intended to assist endocrinologists and other healthcare professionals interested in gender incongruity for individuals seeking gender affirmation as male. A safe and effective GAHT regimen aims to effect masculinising physical features without adverse effects. In this document, we offer suggestions based on an in-depth review of national and international guidelines, recently available evidence and collegial meetings with expert Indian clinicians working in this field. Clinicians represented in our expert panel have developed expertise due to the volume of gender incongruent individuals they manage. This consensus statement provides protocols for the hormone prescribing physicians relating to diagnosis, baseline evaluation and counselling, prescription planning for masculinising hormone therapy, choice of therapy, targets for monitoring masculinising hormone therapy, clinical and biochemical monitoring, recommending sex affirmation surgery and peri-operative hormone therapy. The recommendations made in this document are not rigid guidelines, and the hormone-prescribing physicians are encouraged to modify the suggested protocol to address emerging issues.

Small bowel diverticulosis: imaging appearances, complications, and pitfalls

Diverticula of the small bowel can be categorised as true, with Meckel's being the only example, or false. False small bowel diverticula (SBD) are acquired through herniation of the internal layers of the bowel wall through the muscularis propria. Peri-ampullary duodenal diverticula are a well-recognised example; however, the importance of more distal SBD in the jejunum and ileum is underappreciated, and they are under-reported on cross-sectional imaging. SBD are a known cause of anaemia, malabsorption, and diarrhoea, and there are myriad complications of SBD and Meckel's diverticula, which range in severity from inflammation and perforation to haemorrhage, tumour formation, and obstruction. Before the advent of computed tomography (CT), SBD were readily diagnosed on fluoroscopic oral contrast studies; however, radiologists are less comfortable with their cross-sectional imaging appearances. This imaging review combines our experience of multiple proven cases, with illustrative diagrams and radiological images of SBD to provide distinct imaging characteristics, allowing for confident diagnosis of SBD and their numerous complications. We discuss the importance of SBD as a cause of benign, non-surgical pneumoperitoneum. We additionally provide important pitfalls to be aware of such as SBD masquerading as other abnormalities.

Transgender medicine in primary care

This review focuses on transgender medicine, and its importance in South Asia. It describes the various facets of transgender medicine that are relevant to primary health care providers. The authors call for greater sensitivity towards the needs of the transgender community, so that they can receive quality care at the primary level.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Think before you prescribe: how dentistry contributes to antibiotic resistance

Antibiotic resistance presents a daunting challenge to health professionals worldwide and has the potential to create major problems for modern health care, resulting in more medical expenditure, extended hospital stays and increased morbidity and mortality. Advanced genome sequencing technologies present a complex picture of resistance, extending our understanding beyond the pharmacotherapeutic interface between pathogens and antibiotics. This review discusses the global scope and scale of antibiotic resistance and contextualizes it for the dental practitioner, emphasizing the role we must play in limiting the progression of resistance through antibiotic stewardship and disease prevention.

Abstract P5-12-04: A new method of data analysis to derive DNA methylation signatures that stratify risk of recurrence in triple negative breast cancer

Background: Triple negative breast cancer (TNBC) accounts for 10-17% of all breast cancer and is more likely to be of higher histological grade, poorly differentiated, associated with a higher recurrence rate and with decreased overall survival. The clinical course of a TNBC patient remains difficult to predict, as tumors with homogenous morphological characteristics may vary in response to therapy and have divergent outcomes. Therefore, additional analytical methods are needed to better classify TNBC. Our goal is to refine the analysis of methylome datasets to derive reliable molecular signatures that can distinguish TNBC patients with good outcomes who may benefit from less aggressive treatment, from those with poor outcomes who would be candidates for more aggressive treatments.

Methods: Our laboratory has conducted and reported, in this meeting, results from analysis of 450k methylation array data on a discovery set of 53 high-risk TNBC cases and 62 low-risk controls treated by locoregional therapy alone, as well as 5 normal breast tissue samples. High-risk cases were defined as patients that relapsed within 0.5 to 6.5 years from the time of diagnosis, while low-risk controls had no relapse and >4 year recurrence-free intervals (RFI). In this work, we devised and applied a novel methylation biomarker discovery program named Hypermethylated Outlier Detector (HOD) that emphasizes the selection of highly methylated markers in cases compared to controls, to find a high-risk signature in the TNBC discovery set. The methylation signature identified by HOD was interrogated in a test set of 50 TNBCs (with 16 recurrences) that did not receive chemotherapy, and in a second test set of 131 TNBCs (with 33 recurrences) that did receive chemotherapy.

Results: HOD identified 39 hypermethylated markers (beta >0.20) that could accurately distinguish between the high-risk cases and the low-risk controls in the discovery set of TNBCs (n=115) treated with locoregional therapy alone. In the test set of TNBC (n=50) with no chemotherapy the 39 markers distinguished high from low risk individuals (likelihood ratio test P=0.049). In a second test set of TNBC (n=131) that received chemotherapy the 39 hypermethylated markers again distinguished high from low risk individuals (likelihood ratio test P=0.0043).

Conclusions: We have presented evidence that a methylation signature identified by HOD can be used to identify TNBC patients that have a high-risk of relapse regardless of receiving chemotherapy. This methylation signature could potentially be used to inform physician decisions on therapeutic strategies for TNBC patients. This could ultimately lead to less aggressive treatment given to patients possessing a methylation profile consistent with a better prognosis. Conversely, patients with hypermethylation in the 39 markers will likely benefit from a more aggressive course of treatment.

Citation Format: Downs BM, Cope LM, Fackler MJ, Cho S, Wolff AC, Regan MM, Sukumar S, Umbricht CB. A new method of data analysis to derive DNA methylation signatures that stratify risk of recurrence in triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-12-04.

Abstract P4-08-09: DNA methylation markers predict recurrence-free interval in triple-negative breast cancer

BACKGROUND. Chemotherapy remains the treatment mainstay for triple-negative breast cancer (TNBC). Nevertheless, randomized trials have shown that not all TNBC require it, nor does it benefit all patients that receive it. Molecular tools to risk-stratify TNBC are currently lacking. In light of the importance of epigenetic processes modulating gene expression, we performed an array-based genome-wide DNA methylation search in well-documented institutional and clinical trial cohorts of TNBC for markers that can distinguish breast cancers with a favorable natural history from those with a high risk of recurrence.

METHODS. We performed an array-based genome-wide DNA methylation survey of well-documented institutional and clinical trial cohorts of TNBC and conducted molecular marker discovery on institutional TNBCs (115 patient samples; 53 recurrences) treated by locoregional therapy (LRT) alone. The identified hypermethylated gene signatures were then tested in a TNBC cohort (50 patient samples; 16 recurrences) from the no chemotherapy arms of IBCSG trials VIII and IX, and in a separate combined cohort of TNBCs (131 patient samples; 33 recurrences) treated with chemotherapy from an institutional repository and from IBCSG trials VIII and IX. Cross platform validation was conducted using quantitative multiplexed methylation specific PCR (QM-MSP) on hypermethylated markers in samples from both the Discovery Set and IBCSG LRT Test Set.

RESULTS. We identified methylation signatures in the discovery cohort consisting of 100 or 30 CpG probes that discriminated patients who remained recurrence-free from those with recurrent disease. These signatures were then tested in the IBCSG no chemotherapy cohort, and we found that hypermethylation was associated with shorter recurrence-free interval (RFI). A significant association of both 100 CpG (P<0.0001) and 30 CpG (P=0.0021) signatures with shorter RFI was found in the combined institutional and IBCSG chemotherapy cohort. We observed an enrichment of methylation probes residing on chromosome 19, particularly within 19q13.41-43, that significantly correlated with RFI following chemotherapy. QM-MSP results reflected that of the methylation array [Spearman correlation coefficient of r = 0.495 (P = 0.0009)] indicating that the relationship between high methylation and short RFI is detectable independent of analytical platform. We also observed enrichment for Chromosome 19-specific probes within the 100 and 30 probe sets. While only 5% of all CpG markers are located within Chr19, 15% of the 100 CpG set, 37% of the 30 CpG set, and 47% of the 17 CpGs that are statistically significantly correlated with RFI in the chemotherapy group reside on the Chr19, mostly within 19q13.41-43.

CONCLUSIONS. Methylation markers may be of prognostic importance in TNBC and our findings should be validated in additional clinical trial cohorts.

Citation Format: Fackler MJ, Cho SS, Cope LM, Gabrielson E, Wilsbach K, Lynch C, Marks JR, Geradts J, Regan MM, Viale G, Wolff AC, Umbricht CB, Sukumar S. DNA methylation markers predict recurrence-free interval in triple-negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-08-09.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Primary hyperparathyroidism: insights from the Indian PHPT registry

The presentation of primary hyperparathyroidism (PHPT) is variable throughout the world. The present study explored retrospective data submitted to the Indian PHPT registry ( http://www.indianphptregistry.com ) between July 2005 and June 2015 from 5 centres covering four different geographical regions. The clinical, biochemical, radiological and histopathological characteristics of PHPT patients across India were analysed for similarity and variability across the centres. A total of 464 subjects (137 men and 327 women) with histopathologically proven PHPT were analysed. The mean age was 41 ± 14 years with a female:male ratio of 2.4:1. The majority (95%) of patients were symptomatic. Common clinical manifestations among all the centres were weakness and fatigability (58.7%), bone pain (56%), renal stone disease (31%), pancreatitis (12.3%) and gallstone disease (11%). Mean serum calcium, parathyroid hormone and inorganic phosphorus levels were 11.9 ± 1.6 mg/dL, 752.4 ± 735.2 pg/mL and 2.8 ± 0.9 mg/dL, respectively. Sestamibi scanning had better sensitivity than ultrasonography in the localisation of parathyroid adenoma; however, when these two modalities were combined, 93% of the cases were correctly localised. Mean parathyroid adenoma weight was 5.6 ± 6.5 g (0.1-54 g). It was concluded that the majority of PHPT patients within India are still mainly symptomatic with >50% of patients presenting with bone disease and one-third with renal impairment. Compared to Western countries, Indian patients with PHPT are younger, biochemical abnormalities are more severe, and adenoma weight is higher. As our observation is largely derived from a tertiary care hospital (no routine screening of serum calcium level), the results do not reflect racial differences in susceptibility to PHPT.

Abstract P6-03-07: An automated DNA methylation assay (QM-MSP) for rapid breast cancer diagnosis in underdeveloped countries

BACKGROUND: Underdeveloped countries reported 882,900 new cases of breast cancer and 324,000 deaths in 2012, likely to be a gross underestimation according to recent reports. Often, mammography screening is not available, primary care services are limited, and pathology and treatment services are available only in the regional hospitals. Because of the lack of access to diagnostic and treatment services, it is estimated that more than 90% of patients with breast cancer never present for medical treatment. To address this situation, an accurate, easy-to-perform diagnostic test appropriate for use in remote clinics is desperately needed. Johns Hopkins (JH) and Cepheid partnered to translate a robust Quantitative Multiplex Methylation-Specific PCR (QM-MSP) assay to an automated, cartridge-based system that provides quantitative measures of DNA methylation within hours of fine needle aspiration or core biopsy of image-detected suspicious lesions.

METHODS: With a goal of discriminating malignant from benign breast disease with high sensitivity and specificity, we evaluated 24 breast cancer-specific DNA methylation markers (selected through comprehensive methylome analysis) in 119 invasive ductal carcinomas and 186 benign breast tissues. QM-MSP was performed on sections of formalin-fixed paraffin-embedded (FFPE) tissues to quantify DNA methylation. The dynamic range and performance of quantitative methylation detection was tested using a subset of 9 genes in the cartridge-based system.

RESULTS: QM-MSP was performed in a Training set consisting of 93 tissues [n=43 IDC, n=50 benign lesions (25 usual ductal hyperplasia, UDH, and 25 papilloma)] from the US. We selected 9 DNA markers significantly (p&lt;0.05) more methylated in malignant compared to benign lesions, which had low or no methylation. An independent Test set consisted of benign (n=26) and malignant (n=10) tissues (mostly Caucasian; JH Test Set). As a panel, the 9 markers were significantly more methylated in malignant than benign tissue (p&lt;0.001), revealing a sensitivity of 90% and specificity of 92%, using a laboratory cutoff of 9.5 CMI units (900 unit scale) based on receiver operator characteristic statistics (ROC; p&lt;0.0001, AUC=0.977). To determine if the markers characterized in the JH Test Set could perform as well in samples from a different geography, the panel was tested on 176 tissues from Wuhan, China (China Test Set). In this cohort (66 IDC and 110 benign tissues - 49 fibroadenoma, 19 benign cyst, 12 UDH, 30 papilloma), sensitivity was 89% and specificity was 89% for detection of breast cancer with ROC AUC=0.945. An advanced version of the cartridge with up to 12 methylated DNA markers is under development, thus far showing robust signals in cancer and low background in benign tissues. Current work at JH is focused on optimizing the technical performance of the cartridge.

CONCLUSIONS: We identified a panel of methylated DNA markers that discriminate malignant from benign breast lesions and built a prototype automated cartridge-based assay with promising sensitivity and specificity for breast cancer. Such an assay has the potential to aid in specimen triage in the pathology lab and provide fast, low cost and accurate diagnosis of breast cancer in LMIC settings.

Citation Format: Fackler MJ, Downs BM, Mercado-Rodriguez C, Cimino-Mathews A, Chen C, Yuan J, Cope LM, Kohlway A, Kocmond K, Lai E, Weidler J, Visvanathan K, Umbricht CB, Harvey S, Wolff AC, Bates M, Sukumar S. An automated DNA methylation assay (QM-MSP) for rapid breast cancer diagnosis in underdeveloped countries [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-03-07.

Variants of katG, inhA and nat genes are not associated with mutations in efflux pump genes (mmpL3 and mmpL7) in isoniazid-resistant clinical isolates of Mycobacterium tuberculosis from India

To understand the impact of efflux pump genes such as mmpL3 and mmpL7 on isoniazid (INH) resistance and to correlate with presence or absence of mutations in essential genes of INH resistance (katG, inhA, and nat) in clinical isolates of Mycobacterium tuberculosis (M. tuberculosis). One hundred (75 resistant and 25 sensitive) clinical isolates of M. tuberculosis from India were selected for the study. The presence of mutations in specific regions of katG, inhA, and nat, efflux pump genes (mmpL3 and mmpL7) associated with INH resistance were analyzed using multiplex allele-specific polymerase chain reaction (MAS-PCR) and DNA sequencing methods, respectively. Substitution mutation AGC-ACC at codon 315 of the katG gene was detected in 65% of resistant isolates. Mutation (C-T at nucleotide position 15) in the inhA promoter region was seen in 22% of resistant isolates. Silent mutation (GGA to GGG) at codon 207 in the nat gene was found in three resistant isolates. No mutations were found in either of the efflux genes (mmpL3 and mmpL7) in any of the isolates. Of the 75 resistant isolates analyzed, 74% had mutation in katG and inhA genes. Thus, this report suggests that the role of mmpL3, mmpL7 and nat genes in INH resistance should not be overestimated in comparison to the primary contribution by katG and inhA in clinical isolates of M. tuberculosis. Further, this concise report is the first of its kind to our knowledge, to show the influence of efflux genes on INH resistance in relation to katG and inhA in clinical isolates of M. tuberculosis.

Activation of tumor suppressor LKB1 by honokiol abrogates cancer stem-like phenotype in breast cancer via inhibition of oncogenic Stat3

Tumor suppressor and upstream master kinase Liver kinase B1 (LKB1) plays a significant role in suppressing cancer growth and metastatic progression. We show that low-LKB1 expression significantly correlates with poor survival outcome in breast cancer. In line with this observation, loss-of-LKB1 rendered breast cancer cells highly migratory and invasive, attaining cancer stem cell-like phenotype. Accordingly, LKB1-null breast cancer cells exhibited an increased ability to form mammospheres and elevated expression of pluripotency-factors (Oct4, Nanog and Sox2), properties also observed in spontaneous tumors in Lkb1^-/- mice. Conversely, LKB1-overexpression in LKB1-null cells abrogated invasion, migration and mammosphere-formation. Honokiol (HNK), a bioactive molecule from Magnolia grandiflora increased LKB1 expression, inhibited individual cell-motility and abrogated the stem-like phenotype of breast cancer cells by reducing the formation of mammosphere, expression of pluripotency-factors and aldehyde dehydrogenase activity. LKB1, and its substrate, AMP-dependent protein kinase (AMPK) are important for HNK-mediated inhibition of pluripotency factors since LKB1-silencing and AMPK-inhibition abrogated, while LKB1-overexpression and AMPK-activation potentiated HNK's effects. Mechanistic studies showed that HNK inhibited Stat3-phosphorylation/activation in an LKB1-dependent manner, preventing its recruitment to canonical binding-sites in the promoters of Nanog, Oct4 and Sox2. Thus, inhibition of the coactivation-function of Stat3 resulted in suppression of expression of pluripotency factors. Further, we showed that HNK inhibited breast tumorigenesis in mice in an LKB1-dependent manner. Molecular analyses of HNK-treated xenografts corroborated our in vitro mechanistic findings. Collectively, these results present the first in vitro and in vivo evidence to support crosstalk between LKB1, Stat3 and pluripotency factors in breast cancer and effective anticancer modulation of this axis with HNK treatment.

Female phenotype with male karyotype: a clinical enigma

Development of gonadal and phenotypic sex during embryogenesis invariably corresponds to the genotypic sex. However, some disorders of sex development are associated with discordance between the chromosomal, gonadal or phenotypic sex which include complete androgen insensitivity syndrome, 46XY complete gonadal dysgenesis (Swyer syndrome) and, rarely, congenital adrenal hyperplasia due to CYP 17A1 (17α-hydroxylase) deficiency. The enzyme CYP17A1 includes 17α-hydroxylase and 17,20-lyase which are required for the synthesis of cortisol and sex steroids, respectively. The consequent cortisol deficiency results in a compensatory increase in adrenocorticotropic hormone (ACTH) drive, which stimulates the production of deoxycorticosterone and corticosterone leading to hypertension and hypokalaemia. Concurrent lack of sex steroids results in sexual infantilism without ambiguity. Both the genotypic males and females present during adolescence with a female phenotype, sexual infantilism and hypertension depending on the severity of the enzyme deficiency. We describe a case of CYP17A1 deficiency in a phenotypic female with 46XY karyotype who presented with sexual infantilism but without hypertension.

The microbiology of diabetic foot infections in patients recently treated with antibiotic therapy: A prospective study from India

AIM

Clinicians often treat clinically infected diabetic foot ulcers without information from cultures of the wound. The results of wound cultures may also be affected by previous antibiotic therapy. Thus, we aimed to study the microbial isolates, and antimicrobial sensitivity of previously treated patients with a clinically infected DFU.

RESEARCH DESIGN AND METHODS

293 consecutive patients with clinically infected DFU on prior antimicrobial treatment within the immediate past few days for a duration greater than one week were evaluated for microbial etiology, antibiotic sensitivity and final outcomes. Appropriate tissue samples i.e. purulent drainage, soft-tissue and/ or bone were obtained for aerobic/anaerobic cultures and antimicrobial sensitivities. 71 patients with missing prior antibiotic data were excluded.

RESULTS

313 tissue samples obtained from 222 patients isolated 317 causative organisms. Most of the culture results from tissue specimens were mono-microbial (93.2%) compared to 37% in our previous cohort of 60 patients. Pseudomonas aeruginosa was the most common organism isolated on culture of bone (26.9%) or soft tissue (23.2%) specimen, respectively. Only 23% and 64% of P. aeruginosa isolates and 5.6% and 44% of Acinetobacter sp. were sensitive to quinolones and cephalosporins, respectively.

CONCLUSIONS

Clinically infected DFU recently treated with antibiotics have predominant monomicrobial and multi drug-resistant infection. Quinolones as an empirical antibiotic choice may not be appropriate in this setting.

Dynamic nuclear polarization of biocompatible (13)C-enriched carbonates for in vivo pH imaging

A hyperpolarization technique using carbonate precursors of biocompatible molecules was found to yield high concentrations of hyperpolarized (13)C bicarbonate in solution. This approach enabled large signal gains for low-toxicity hyperpolarized (13)C pH imaging in a phantom and in vivo in a murine model of prostate cancer.

Mitigation of environmental impacts due to ghat road formation in Palamalai Hills, South India, by optimizing cut and fill volumes using GPS and GIS techniques

Formation of new roads generally brings about adverse impact on the environment, and in the case of hill roads, the impact is diverse and effective measures are required to mitigate it. The common problems in hill road formation are tree cutting, destruction of canopies, change in land use pattern, soil erosion, slope instability, induced landslides, invasion of foreign species, and so on. Removal of trees and vegetations causes rapid soil erosion, landslides, and invasion of foreign species posing danger to the survival of weak native species. Dumping of surplus earth materials on the valley side poses a significant threat to the environment as it would cause induced landslides. Using the cut earth for filling in road formation and dumping, the surplus cut earth in safe locations will reduce environmental degradation considerably. Conventionally, hill road alignments are finalized using traditional survey methods using ghat tracer, compass, and leveling surveys which require enormous complicated field and office works. Any revision to reduce the quantum of earthwork is difficult in this method due to its complex nature. In the present study at Palamalai Hills, South India, an alignment for a length of 7.95 km was prepared by traditional methods using ghat tracer and total station instruments for survey works. The earthwork quantities were ascertained from the longitudinal profile of the alignment. A GPS survey was also conducted along the alignment to examine its utility in alignment modification. To modify the stretches, where the earthwork cutting and filling are above normal and unbalanced and result in surplus earth, repeated GPS surveys were conducted along different paths to optimize the earthwork. The earthwork quantities of the original alignment were analyzed, and its correlation with environmental effect and the usefulness of the GPS survey in this task are presented in this paper.

Abstract P2-06-01: cMethDNA is a quantitative circulating methylated DNA assay for detection of metastatic breast cancer and for monitoring response to therapy

Background- The ability to consistently detect cell-free tumor-specific DNA in peripheral blood of patients with metastatic breast cancer provides the opportunity to detect changes in tumor burden and to monitor response to treatment. Studies of cell-free DNA in the peripheral blood of breast cancer patients suggest that methylated DNA markers in serum or plasma could be used for detection of advanced disease, monitoring of therapeutic response, and for early detection of disease recurrence.

Methods- A genome-wide serum DNA methylome array (Illumina HumanMethylation27 BeadChip) analysis was conducted on cell-free circulating DNA in serum from women with stage IV recurrent breast cancer, and 232 key CpG loci were identified. Methylation for this panel of 10 gene loci was evaluated using our newly developed cMethDNA assay to detect miniscule amounts of methylated DNA in Training and Test sets of sera from a total of 112 women (n = 55 normal, n = 57 metastatic breast cancer). The clinical sensitivity and specificity of the assay, along with technical reproducibility, was determined. To evaluate the concordance of DNA methylation patterns, the 10 gene panel was tested on 22 DNA sets of primary tumor, metastases and serum from the same patient. Finally, the ability of cMethDNA to monitor response to therapy was evaluated in 28 patients with metastatic disease.

Results- A normal laboratory threshold of 7 cumulative methylation units was set and assay parameters were locked, based on Receiver Operating Characteristic (ROC) analyses of DNA from 300 ul of patient sera in the Training set (normal, n = 28; cancer, n = 24; 92% sensitivity, 96% specificity, and AUC = 0.950). Evaluation of the Test set of patient sera (normal, n = 27; cancer n = 33) resulted in detection of metastatic breast cancer with 91% sensitivity, 100% specificity, and AUC = 0.994 (0.984-1.005, p&lt;0.0001). Reproducibility of the cMethDNA assay increased with copy number; with the highest variation at 50 copies (CV = 29.1%) and the lowest at 3,200 copies (CV = 2.5%) of methylated DNA. The test was shown to be operator independent (ICC = 0.99). Evaluation of concordance between primary and disseminated tumor methylation showed that the methylation pattern from any given individual is highly conserved between serum, primary tissue and their metastases, and poorly conserved between different individuals. cMethDNA analysis of 28 patients before and after initiation of therapy showed a decrease in cumulative methylation in women with stable/responsive disease and a correlation with disease progression free survival (p&lt;0.0001).

Conclusion- Together, our data suggest that the cMethDNA test 1) can detect tumor DNA shed into blood, 2) reflect the methylation alterations typical of the primary tumor and its metastatic lesions, and 3) reflect response to treatment after chemotherapy. Next, we will test the clinical utility of cMethDNA in independent clinical trial sample sets where it's complementary and independent roles will be examined against CA15.3 and CTC assays.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-06-01.

Abstract P3-01-01: Targeting glutamine metabolism in breast cancer for therapy

Metabolic reprogramming of cancer cells is observed in different types of tumors including breast. Oncogenic signals aid changes in metabolism that provide selective advantage to the cancer cells to meet their energy requirements to accomplish rapid proliferation. The increased dependence on the glycolytic pathway for energy called the “Warburg effect” was reported by Otto Warburg several decades ago. Our recent understanding of cancer metabolism has thrown light on alternative energy sources, especially glutamine and other branched chain amino acids. The role of glutamine in breast cancer cell growth has not yet been studied extensively.

In this study we found that a number of breast cancer cell lines, especially those negative for ER, PR, HER2, display a high dependence on glutamine for their survival and growth. Interestingly, most of these glutamine-dependent cell lines express high levels of c-myc protein. Consistent with their growth dependency on glutamine, transaminases responsible for entry of glutamine into the tricarboxylic acid cycle are transcriptionally up regulated under low glutamine conditions. Consequently, growth of these cancer cell lines was found to be specifically inhibited by the transaminase inhibitor, amino oxyacetate (AOA). Moreover, the AOA mediated cytotoxic effect was partially c-myc dependent. Through 1H-NMR studies of AOA-treated cells we show that in addition to glutamine, AOA treatment decreases the aspartate and alanine content in the cells. In line with these findings, exogenous supplementation with aspartate partially rescued the cells from the growth inhibitory effects of AOA. Flow cytometry analysis showed that AOA causes cell cycle arrest in the S phase. AOA also had significant inhibitory effect on in vivo growth of rapidly growing SUM 149 and SUM159 xenografts in immunodeficient mice. When combined with chemotherapeutic agents, doxorubicin and carboplatin, AOA inhibited growth of MDA-MB-231 xenograft tumors more effectively than AOA alone. Lastly we present evidence that the cytotoxic effect of AOA is mediated through activation of the ER stress pathway, combined with depletion of key amino acids and likely, a reduction in the nucleoside pool in the cells. Our preclinical studies, both in vitro and in vivo, combined with development of intermediate markers of response, provide a strong rationale for testing AOA for therapy in Phase 0 clinical trials.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-01-01.

Areca nut chewing in an expatriate population in Sydney: report of two cases

Areca nut (betel nut) consumption occurs in a variety of forms, either on its own or with the addition of a number of products. This habit is prevalent in the Indian Subcontinent and South-East Asia. Recent immigration statistics indicate that 30% of new arrivals in Australia are from these geographical regions and are known to perpetuate this custom long after migration. The objective of this paper is to highlight the variety of oral presentations that may occur as a result of areca nut consumption in these particular demographic subgroups. Dental practitioners must be familiar with the wide spectrum of oral lesions that may present in this setting. More significantly, they must be aware that some of these lesions possess the potential for malignant transformation and hence require more specific management. Best practice mandates that dental practitioners in a multicultural society must: (1) be capable of recognizing the expatriate populations in which this custom is widely practised; (2) incorporate this particular line of questioning into the routine risk factor analysis that is undertaken for every patient from these particular sub-populations; and (3) institute appropriate referral and follow-up of these lesions if required.

Abstract P4-08-08: HOXC10, a homeobox protein overexpressed in breast cancer, modulates the response to chemotherapy treatment

Background: Breast cancer is the second leading cause of cancer deaths in women worldwide. Although chemotherapy is effective, resistance to drugs develops over time and can account for treatment failure in over 90% of metastatic breast cancer patients. HOX genes are homeobox-containing transcription factors well-known for their role in morphogenesis. and during carcinogenesis and metastasis. The goal of this study is to understand the role of HOXC10 in breast cancer and mainly in response to chemotherapy.

Methods: Using a tiling array of all four HOX clusters in a panel of primary and metastatic breast cancer tissues, we identified HOXC10 as being among the highly overexpressed genes in breast cancer. Then using a panel of cell lines that either stably overexpress exogenous HOXC10 or cell lines with stably downregulated endogenous HOXC10 (mediated by shRNA), we investigated the role of HOXC10 in proliferation, response to chemotherapy treatment and repair of DNA damage.

Results: HOXC10 is overexpressed in 67% of primary breast tumors (n = 31), in 82% of the metastatic tissues (n = 49) and in most breast cancer cell lines (n = 48). In vitro and in vivo investigation confirmed that HOXC10 plays an oncogenic role in breast cancer. Further, knockdown of HOXC10 in a panel of breast cancer cell lines slowed their proliferation and arrested them at the G1 phase, by inactivating the RB/E2F pathway, decreasing the number of new origins and eventually reducing the polyploidy population.

Cell survival assays after different chemotherapeutic drug treatment showed that overexpression of the exogenous HOXC10 in MCF10A led to less susceptibility to most drugs. This was partially due to a protection from apoptosis by upregulating and activating the anti-apoptotic machinery such as the NF-kb pathway. Further investigation revealed the involvement of HOXC10 in DNA repair (and not initial response), especially after DNA crosslink damage. Interestingly, the binding of HOXC10 to CDK7 in a region outside its homeodomain activates CDK7 activity towards RNA polymerase II mainly in response to DNA damage. Since HOX genes are difficult to target therapeutically, one potential approach to overcome chemoresistance in HOXC10 overexpressing cells is by including CDK7 inhibitors (already in clinical trials).

All these results were confirmed in the SUM159 model which stably expresses a HOXC10-shRNA.

Finally, HOXC10 was found to be significantly overexpressed in MCF7 isogenic cell lines gradually selected to be resistant to some chemotherapeutic drugs. By knocking down HOXC10 in these sublines, resistance to the drug was reduced. Further, SUM159 and MDAMD231 xenografts that were treated with chemotherapy over weeks and that show partial to no response tend to have a higher expression of HOXC10.

Conclusion: This study shows that HOXC10, a homeobox protein previously shown to be regulated during the cell cycle and to have a positive effect on proliferation, is overexpressed in the majority of breast cancers. This upregulation may have clinical implications since cells with higher expression of HOXC10 tend to have more genomic instability and activation of anti-apoptotic and DNA repair pathways, which eventually modulate the response to some chemotherapy drugs.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-08-08.

Abstract P2-09-01: Reactivation of epigenetically silenced retinoic acid receptor-beta for therapy of breast cancer- from molecular mechanism to potential clinical applications

Background: Triple negative breast cancer (TNBC) is a subgroup of breast cancer that is characterized by a lack of expression of targets for validated targeted therapies. Although responses to chemotherapy are observed, resistance develops rapidly. Genomic and molecular profiling of TNBC has identified multiple contributors to their uncontrolled growth including epigenetic dysregulation of genes important for normal cell growth and differentiation. Recent studies have shown that histone deacetylase (HDAC) inhibitors reverse the epigenetic profile of tumors, resulting in the re-expression of silenced genes encoding proteins such as ERα, EGFR, and RARβ. Entinostat is an oral, class 1 isoform selective HDACi recently shown in a phase 2 study to be active in ER+ breast cancer. Clinical trials with entinostat in HER2+ and TNBC are also in progress. We hypothesized that combining epigenetic therapy using entinostat, with differentiation therapy using a retinoic acid receptor agonist- All Trans Retinoic Acid (ATRA) will provide an effective strategy for impeding the growth of TNBC and potentially sensitize tumors to commonly used chemotherapies (doxorubicin, carboplatin, paclitaxel).

Methods: Combination studies of entinostat combined with ATRA with and without non-toxic doses (half clinical) of chemotherapy were carried out in vitro and in xenograft models of TNBC. Expression of RARb and downstream effectors were measured in cell lines and tumors from xenograft studies.

Results: Nontoxic (half clinical) doses of doxorubicin when combined with entinostat and ATRA in vitro and in vivo exerted the best response when compared with combinations using paclitaxel and carboplatin. Re-expression of the silenced RARβ and downstream effectors was observed in the cell lines treated in vitro and in tumor xenografts of MDA-MB-231 and SUM159 cells in vivo. To gain insight into mechanism of action for the entinostat – doxorubicin combinations we examined the expression of enzyme targets of doxorubicin and determined that entinostat treatment reduced the expression of topoisomerase (Topo) II enzymes. Besides its conventional role in cell replication and division, Topo II has an important function in regulating transcription, especially in the nuclear receptor pathways such as ER and RAR. Our results demonstrated that Topo IIβ has a dual role in regulating the expression of RARβ. Inhibition of Topo IIβ in a time- and dose dependent manner up-regulated the expression of RARβ and its downstream genes. However, completely eliminating Topo IIβ decreased expression of RARβ.

Conclusions: Our detailed study provides a new approach to treating TNBC using combinations of nontoxic doses of chemotherapeutic drugs with epigenetic therapy, and a deeper understanding of the molecular pathways involved in this response. These results suggest that combination of entinostat and a retinoic acid receptor agonist with low dose doxorubicin will provide an effective strategy for treatment of TNBC.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-09-01.

Abstract P2-02-01: Accurate identification of metastatic breast cancer using methylated gene markers in circulating free DNA in peripheral blood

Background: Preliminary studies from our lab have shown that a panel of methylation markers in tissue identifies 100% of tested breast cancer and 95% of tested DCIS, and has high accuracy in cells from ductal fluid and spontaneous nipple discharge1,2. Other groups have reported on the use of a single marker or a panel of markers to detect breast cancer in serum or plasma. Cell-free DNA studies in the peripheral blood of breast cancer patients with advanced disease or with early-stage disease after completion of local therapy support the hypothesis that methylated DNA markers in serum or plasma could be used to monitor response to therapy and for long-term surveillance. Validation studies to test these hypotheses have been hampered by assay methodological issues such as the very small amount of DNA shed in the serum by tumor compared to the total DNA shed by normal cells.

Methods: To overcome this problem, we developed a modified quantitative methylation-specific PCR that directly measures the number of copies of methylated DNA markers in a small aliquot of serum (Serum-QM-MSP) and robustly detects less than 25 copies of DNA in 300 µL of serum. We then conducted a genome-wide methylome analysis to identify key markers that are preferentially methylated in serum from women with breast cancer and compared the profiles to those from women with no breast cancer. We then analyzed 300 µL each of sera from 55 normal women (single time point) and 43 women with metastatic breast cancer using this newly developed panel of markers and the Serum-QM-MSP assay. We also examined changes after therapy in a subset of patients with metastatic disease.

Results: Methylation markers were quantitatively detected in sera of 39 out of 43 (91% sensitive) metastatic breast cancer patients with varying tumor burdens, and not in sera of any of 55 women (100% specific) for an AUC=0.95, using a laboratory threshold of 7.2 cumulative methylation units. 28 of the 43 patients had sampling repeated 3–5 weeks after therapy started. Sera from patients whose tumors regressed and from those that had stable disease showed a quantitative reduction, while those with progressive disease showed an increase in methylation levels of several genes.

Conclusion: Our results suggest that methylated DNA in serum accurately discriminates between blood samples from normal women and from metastatic breast cancer patients. Also, early changes after therapy initiation for metastatic disease may correlate with subsequent clinical outcome. Assay analytical validation studies are ongoing. Studies examining a potential role in surveillance in the adjuvant setting and therapeutic benefit in the metastatic setting are warranted.

1. Fackler MJ et al. Genome-wide methylation analysis identifies genes specific to breast cancer hormone receptor status and risk of recurrence. Cancer Res. 2011 Oct 1;71(19):6195–207. PMCID: PMC3308629. 2. Fackler MJ, et al. Hypermethylated genes as biomarkers of cancer in women with pathologic nipple discharge. Clin Cancer Res. 2009 Jun 1;15(11):3802–11. PMID: 19470737

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-02-01.

Abstract P4-12-04: Association of single-strand breaks (SSBs) in normal breast DNA with estimates of breast cancer risk

Background: Formation of single strand breaks in DNA is a constant process, estimated to occur 10,000 times per day in each cell, either from endogenous biosynthetic errors or from interference by endogenous or exogenous agents. Base excision repair in some cases may be impaired or may be exceeded by the rate of DNA damage, leading to cancer. Nick translation of with labeled nucleotides can be used as a quantitative indicator of SSBs.

Methods: Healthy women were recruited through the Love-Avon Army of Women and breast clinics of Northwestern and John Hopkins Universities. Digital or digitized mammograms were evaluated for percent density using Cumulus software. The medians (ranges) were age 51 (36 to 60); BMI 28.2 (18.7 to 51.3); life-time Gail estimate 12.5 (5.6 to 28.3); % breast density 16.5 (2.4 to 52.5); Masood score 13 (0 to 18). Breast tissue was obtained by random fine needle aspiration (rFNA). Specimens were rinsed into ice-cold phosphate buffered saline and were stored at −80°C. Thawed samples were centrifuged at 2200 g for 60 min. A kit from Norgen Inc., was used to separate DNA, RNA, and protein from the pellet. The lipids were extracted with ethyl acetate-hexane (3:2) from the supernatant fluid, and triglycerides were precipitated from cold 90% methanol, leaving a purified lipid fraction containing the steroids. Steroids were then fractionated by HPLC on a C18 column, and estradiol was analyzed by a radioimmunoassay. Blood was obtained at the same time as the rFNA samples and was frozen prior to analysis. An aliquot containing 200 ng of DNA (260/280 ratio 1.3 to 2.3) was taken for the nick translation assay. Incorporation of free nucleotides at SSBs with dCTP labeled with3H was catalyzed by Polymerase I from E. coli. A quality control preparation prepared from calf thymus DNA and a reagent blank without DNA was included with each set of 6 samples. Incorporation of3H-dCTP was linear with dose of DNA and reached a maximal at 30 min. Separation of free from incorporated3H-dCTP was accomplished by gel chromatography on an 80 × 15 mm column. The concordance of interassay values was 0.96.

Abstract P3-04-08: Expression of hormone-responsive genes in benign breast tissue varies with menstrual cycle phase and menopausal status

Background: The expression of many genes is known to be regulated by ambient hormone levels. In a preliminary study of random fine-needle aspirate (rFNA) samples from benign breast tissue, we found several genes that were highly correlated with the serum levels of progesterone (P4) and estradiol (E2). We now present data to further validate these genes as markers of menstrual cycle phase (MCP) and menopausal status (MPS) in benign breast tissue which may allow retrospective classification of archived breast samples with respect to MCP and MPS at the time of sampling.

Methods: 240 rFNA samples from healthy women with recorded hormonal data at the time of sampling were analyzed. We divided these subjects by menstrual cycle phase (MCP) and menopausal status (MPS): 41 early follicular: (low circulating E2 and P4); 48 mid-cycle (high E2 and low P4); 31 luteal (moderate E2 and high P4). 120 post-menopausal (low E2 and low P4). 100 ng of RNA from rFNA samples of the breast was reverse transcribed. Amplicons of interest were linearly amplified to 14 cycles for 35 genes related to hormone responsiveness. qPCR reactions were carried out using the TaqMan OpenArray (Applied Biosystems). For each gene of interest, expression levels were normalized to the average expression of GAPDH. Gene expression difference between groups were conducted using the Mann-Whitney Test. P-values from gene expression difference were adjusted via the Benjamini-Hochberg (1995) approach.

Results: The mean value of TNFSF11 expression level was 13.19 fold higher in luteal phase subjects than in post-menopausal subjects (p = 0.0003) where there was also the biggest difference of serum P4 level between groups. The expression of DIO2 and MYBPC1 was also significantly higher in luteal phase group than in the post-menopausal group (p = 0.005, p = 0.02, respectively). These 3 genes also demonstrated a higher expression pattern in luteal phase than mid-cycle and follicular phase but analysis is still ongoing. All comparisons between these groups will be presented at the meeting.

Conclusion: The expression levels of TNFSF11, DIO2 and MYBPC1 vary with MCP and MPS. These hormone-responsive genes are candidate MCP classifiers which could be applied to archived breast samples to assess whether biomarkers of breast cancer risk are stable across the menstrual cycle, since MCP and MPS variation is likely an important source of biological noise in studies of archived breast biopsy material.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-04-08.

Malignant tumours of the jaws

Almost all variants of malignant primary and secondary tumours of bone have been described as occurring within the jaws. Odontogenic carcinomas and sarcomas are peculiar to the jawbones and are distinctly uncommon. Non-odontogenic tumours in comparison arise with more frequency, yet the maxilla and mandible remain unusual sites for most primary and secondary non-odontogenic tumours of bone. The most commonly occurring primary bone tumours affecting the jaws include osteosarcoma, Burkitt's lymphoma and multiple myeloma, while secondary or metastatic tumours to the jaws are rare in contrast to the remainder of the skeleton.

Flexible sigmoidoscopy does not significantly increase polyp and cancer detection yield when used to supplement CT colonography

BACKGROUND AND AIMS

Flexible sigmoidoscopy (FS) increases polyp and carcinoma detection in addition to double contrast barium enema (DCBE). However, CT colonography (CTC) is now the preferred technique. Our aim was to explore whether FS increases polyp and carcinoma detection rates when used in addition to CTC.

METHODS

Patients who underwent FS and CTC between 2007 and 2009 were included and data were collected from patient records. Yields of polyp, adenoma and carcinoma detection were calculated for FS and CTC.

RESULTS

In a cohort of 294 patients, CTC detected 36 patients with carcinomas while FS detected 28. One rectal cancer not seen on CTC was diagnosed by FS. Polyps were seen by CTC in 66 and FS in 45 patients. In 5 patients FS found polyps that were not detected by CTC; 3 of which were small adenomas. FS detected extra adenomas or carcinomas in 1.36% (4/294). Adding FS to CTC neither increased the cancer nor the polyp detection yield significantly.

CONCLUSIONS

This first study investigating the use of FS in addition to CTC detected little additional pathology. The routine use of FS as a supplement to CTC for adenoma and carcinoma detection is of questionable utility.