Severe CNS involvement in a subset of long-term treated children with infantile-onset Pompe disease

INTRODUCTION

The standard of care for patients with infantile-onset Pompe disease (IOPD) is enzyme replacement therapy (ERT), which does not cross the blood brain barrier. While neuromuscular manifestations of IOPD are well-described, central nervous system (CNS) manifestations of this disorder are far less characterized. Here we describe severe CNS-related neurological manifestations including seizures and encephalopathy in six individuals with IOPD.

METHOD

We identified six children with IOPD who developed CNS manifestations such as seizures and/or encephalopathy. We studied their brain magnetic resonance imaging scans (MRIs) and graded the severity of white matter hyperintensities (WMHI) using the Fazekas scale scoring system as previously published. Longitudinal cognitive measures were available from 4/6 children.

RESULTS

All six IOPD patients (4 males/2 females) had been treated with ERT for 12-15 years. Seizures and/or encephalopathy were noted at a median age at onset of 11.9 years (range 9-15 years). All were noted to have extensive WMHI in the brain MRIs and very high Fazekas scores which preceded the onset of neurological symptoms. Longitudinal IQ scores from four of these children suggested developmental plateauing.

DISCUSSION

Among a subset of IOPD patients on long-term ERT, CNS manifestations including hyperreflexia, encephalopathy and seizures may become prominent, and there is likely an association between these symptoms and significant WMHI on MRI. Further study is needed to identify risk factors for CNS deterioration among children with IOPD and develop interventions to prevent neurological decline.

New Insights into Gastrointestinal Involvement in Late-Onset Pompe Disease: Lessons Learned from Bench and Bedside

BACKGROUND

There are new emerging phenotypes in Pompe disease, and studies on smooth muscle pathology are limited. Gastrointestinal (GI) manifestations are poorly understood and underreported in Pompe disease.

METHODS

To understand the extent and the effects of enzyme replacement therapy (ERT; alglucosidase alfa) in Pompe disease, we studied the histopathology (entire GI tract) in Pompe mice (GAAKO 6^neo/6^neo). To determine the disease burden in patients with late-onset Pompe disease (LOPD), we used Patient-Reported Outcomes Measurements Information System (PROMIS)-GI symptom scales and a GI-focused medical history.

RESULTS

Pompe mice showed early, extensive, and progressive glycogen accumulation throughout the GI tract. Long-term ERT (6 months) was more effective to clear the glycogen accumulation than short-term ERT (5 weeks). GI manifestations were highly prevalent and severe, presented early in life, and were not fully amenable to ERT in patients with LOPD (n = 58; age range: 18-79 years, median age: 51.55 years; 35 females; 53 on ERT).

CONCLUSION

GI manifestations cause a significant disease burden on adults with LOPD, and should be evaluated during routine clinical visits, using quantitative tools (PROMIS-GI measures). The study also highlights the need for next generation therapies for Pompe disease that target the smooth muscles.

Novel approaches to quantify CNS involvement in children with Pompe disease

OBJECTIVE

To characterize the extent of CNS involvement in children with Pompe disease using brain MRI and developmental assessments.

METHODS

The study included 14 children (ages 6-18 years) with infantile Pompe disease (IPD) (n = 12) or late-onset Pompe disease (LOPD) (n = 2) receiving enzyme replacement therapy. White matter (WM) hyperintense foci seen in the brain MRIs were systematically quantified using the Fazekas scale (FS) grading system with a novel approach: the individual FS scores from 10 anatomical areas were summed to yield a total FS score (range absent [0] to severe [30]) for each child. The FS scores were compared to developmental assessments of cognition and language obtained during the same time period.

RESULTS

Mild to severe WM hyperintense foci were seen in 10/12 children with IPD (median age 10.6 years) with total FS scores ranging from 2 to 23. Periventricular, subcortical, and deep WM were involved. WM hyperintense foci were seen throughout the path of the corticospinal tracts in the brain in children with IPD. Two children with IPD had no WM hyperintense foci. Children with IPD had relative weaknesses in processing speed, fluid reasoning, visual perception, and receptive vocabulary. The 2 children with LOPD had no WM hyperintense foci, and high scores on most developmental assessments.

CONCLUSION

This study systematically characterized WM hyperintense foci in children with IPD, which could serve as a benchmark for longitudinal follow-up of WM abnormalities in patients with Pompe disease and other known neurodegenerative disorders or leukodystrophies in children.

Behavioral, social and school functioning in children with Pompe disease

Purpose

To improve our understanding of the behavioral, social, and emotional functioning of children and adolescents with Pompe disease.

Method

Parents/guardians of 21 children (age 5-18y) with infantile (IPD) or late-onset (LOPD) Pompe disease on long-term enzyme replacement therapy completed three standardized checklists regarding their child's behavior: the Child Behavior Checklist (CBCL), Conners 3 Parent (Conners-3), Behavior Rating Inventory of Executive Function-2 (BRIEF2), and a survey of their child's educational services.

Results

Descriptive statistics were used to summarize the findings for each behavior checklist. Age standard scores from each checklist were reported for the IPD (n = 17, 9 females, mean age = 9y, 4 mo; SD = 3y, 8mo) and LOPD (n = 4, 1 female; mean = 11y, 2mo; SD = 2y, 1mo) groups. The majority of children with Pompe exhibited age-appropriate behavior and emotional functioning on these standardized checklists. However, negative mood symptoms, learning problems, decreased participation in structured social activities, and attentional difficulties were more frequently reported in children with IPD in comparison to same-aged peers. Parents of children with LOPD reported fewer problematic behaviors but endorsed negative mood symptoms and difficulties with peer relations. Most children received accommodations in regular education classrooms at school.

Conclusions

These standardized behavior checklists are useful screening tools for the early identification and treatment of behavior, emotional, and social concerns in children with Pompe disease.

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Parents of children with Pompe disease completed standardized behavior checklists.

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Most children with Pompe exhibited age appropriate behavior and emotional functioning.

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Negative mood, learning, and attentional problems reported in infantile Pompe group.

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Negative mood and concerns about peer interactions reported in late-onset Pompe group.

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Most children with Pompe attend and succeed at school, with classroom accommodations.

An emerging phenotype of central nervous system involvement in Pompe disease: from bench to bedside and beyond

Pompe disease (PD) is a lysosomal storage disorder caused by deficiency of the lysosomal enzyme acid-alpha glucosidase (GAA). Pathogenic variants in the GAA gene lead to excessive accumulation of lysosomal glycogen primarily in the cardiac, skeletal, and smooth muscles. There is growing evidence of central nervous system (CNS) involvement in PD. Current research is focused on determining the true extent of CNS involvement, its effects on behavior and cognition, and effective therapies that would correct the disease in both muscle and the CNS. This review article summarizes the CNS findings in patients, highlights the importance of research on animal models, explores the probable success of gene therapy in reversing CNS pathologies as reported by some breakthrough preclinical studies, and emphasizes the need to follow patients and monitor for CNS involvement over time. Lessons learned from animal models (bench) and from the literature available to date on patients will guide future clinical trials in patients (bedside) with PD. Our preliminary studies in infantile PD show that some patients are susceptible to early and extensive CNS pathologies, as assessed by neuroimaging and developmental assessments. This article highlights the importance of neuroimaging which could serve as useful tools to diagnose and monitor certain CNS pathologies such as white matter hyperintense foci (WMF) in the brain. Longitudinal studies with large sample sizes are warranted at this time to better understand the emergence, progression and consequences of CNS involvement in patients with PD.

Abstract P4-10-12: Treatment decision making, and strategies for coping with financial stress in Indian women diagnosed with breast cancer and their families

Introduction: In spite of rapid urbanization and modernization the family remains central in the socio-cultural structure of India. The individuals are enmeshed into this unit and tend to be interlinked financially, emotionally and socially. The head of this family unit tends to be a male more often than not. As is well known, despite recent attempts by the governments at the state and centre at providing health coverage for cancer through regional cancer centres, a majority have to raise the money for cancer care by themselves. We have examined the role of the family in treatment decision making and in the strategies employed to raise the money and cope with the financial stress imposed by a diagnosis of breast cancer.

Method: 378 women with breast cancer were enrolled into a longitudinal study at first diagnosis between the years 2008-2012, at two tertiary care hospitals in Bangalore, India. The median follow up as of May 31st 2017 is 78 months with only 2% loss to follow-up over the past 8 years. Follow-up was maintained by frequent meetings between a counselling psychologist (AA) and the patient and/or a family member. The frequency of meetings was monthly during the initial treatment and then quarterly over the next 5 years. Information on demographics was collected during the treatment phase and information on the psychosocial aspects was collected in non-structured interactions subsequently. This information included details of support structure, decision making, and financial arrangements.

Results: This is a predominantly urban cohort with 80% being urban. The median age of patients at first diagnosis was 55 years. Almost all of our patients (99%) had the support of one or more family members. We analysed the pattern of decision making for treatment and in half of all cases either the husband or the son were the decision makers. In an additional 15% daughters and other relatives were the primary decision makers. Approximately a third of women made the decision concerning treatment themselves, and these women tended to be college educated (51% vs 16%) and employed (53% vs 12%).

30% of the patients met the costs incurred through medical insurance plans purchased by the family. Another quarter of patients were able to meet the costs from their savings. 45% had difficulty in finding the money for treatment and 15% took personal loans while 30% had to sell land/gold ornaments or take loans against assets of these sorts. Only (3%) discontinued the treatment due to financial difficulties. As in the case of decision making those who had the financial resources tended to be more educated (41% vs 11%), and were employed (31% vs 21%).

Conclusion: The data from a predominantly urban cohort of breast cancer enrolled between 2008-2012, supports the general belief that in India the family remains the fulcrum of an individual during crises, and not surprisingly education and employment lead to both psychological and economic emancipation of women.

Citation Format: Alexander A, Kaluve R, Prabhu JS, Korlimarla A, BS S, Manjunath S, Patil S, KS G, Sridhar TS. Treatment decision making, and strategies for coping with financial stress in Indian women diagnosed with breast cancer and their families [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 P4-10-12.

Abstract P4-07-10: Epithelial mesenchymal transition associated with high miR-221 and integrin β6 leads to poor prognosis in hormone receptor positive HER2 negative breast cancers

Background: MicroRNA mediated molecular alterations are involved in the initiation and progression of cancer. Altered expression of multiple microRNAs is associated with endocrine resistance in hormone receptor positive HER2 negative (HR+/HER2-ve) cancer. The role of miR-221 in inducing epithelial to mesenchymal transition (EMT) is well documented especially in cell line model systems. However, the detailed mechanism of specific microRNAs in intrinsic and acquired resistance to endocrine therapy needs to be worked out. In addition, more needs to be done in the documentation of these mechanisms in human breast cancer specimens with complete clinical documentation and long-term follow-up. In this study, we have evaluated the clinical significance of miR-221 and its mechanistic role in EMT using human specimens and cell line models.

Materials and Methods: Formalin fixed paraffin embedded tumor from 129 HR+/HER2-ve breast cancer patients with a median follow up of 63 months were used for estimation of miR-221 by quantitative real time PCR. Expression levels of genes which are direct targets of miR-221 and related genes in EMT were analysed from these tumors. Survival between miR-221 high and low groups was compared by Kaplan Meier survival curves and prognostic relevance was estimated by Cox proportional hazard model.

Cell line experiments to investigate the role of miR-221 in inducing EMT through integrin β6 are underway in both wild type and tamoxifen resistant MCF-7 cell lines (A gift from Prof Ben Ho Park, Johns Hopkins University School of Medicine).

Results: A significant elevated level of miR-221 was observed in small proportion (14%) of HR+/HER2-ve tumors. miR-221 expression had an inverse correlation with both ER protein and ESR1 mRNA levels within HR+/HER2-ve tumors. Tumors with high levels of miR-221 showed significantly higher expression of integrin β6 which is a robust marker of EMT. Patients with high expression of miR-221 had a poorer survival in Kaplan Meier analysis.

Results of interrogation of EMT mediated through integrin related pathways involving miR-221 in cell line models will be presented.

Discussion: The association between miR-221 and integrin β6 in HR+/HER2-ve breast cancer with endocrine resistance suggests a potential link between an epigenetic regulator and a mediator of tumor-stromal interaction. The other mediators involved in this pathway are being investigated. miR-221 could be potentially used as a marker for identification of a poor prognostic subtype within HR+/HER2-ve breast cancers.

Citation Format: Prabhu JS, Kaul R, Korlimarla A, Desai K, Gangadharan C, Rajarajan S, Nair MG, Alexander A, Kaluve R, Manjunath S, Correa M, Prasad MSN, Patil S, Srinath BS, Sridhar TS. Epithelial mesenchymal transition associated with high miR-221 and integrin β6 leads to poor prognosis in hormone receptor positive HER2 negative breast cancers [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-07-10.

Abstract P4-06-11: Differential regulation of microRNAs and integrins influences metastatic potential: Comparison between locally invasive BT-474 and metastatic MDA-MB-231 xenografts

Background: Generation of BT-474 and MDA-MB-231 xenografts in immunocompromised mice provides one means of dissecting the molecular events involved in local invasion versus distant metastasis. Recently, Glunde et al have shown an interdependence of genes involved in cell-cell and cell-matrix adhesion (E-cadherin and integrin β1) and extra-cellular matrix degradation (MMP-2 and 9) in allowing cells to metastasize. Further, Fite el al have identified a set of microRNAs (miRs) up-regulated by E-cadherin (a pre-EMT marker) and down-regulated by Vimentin (post-EMT marker) in acquiring an invasive phenotype. We have performed a detailed analysis of integrins, matrix metallo-proteases and key miRs to better understand the molecular events underlying these disparate behaviours.

Methods: We injected BT-474 (N=5) and MDA-MB-231 (N=5) cells orthotopically into SCID mice. Xenografts were assessed for local growth rate and monitored for distant metastasis. The implanted tumors as well as the distant metastatic foci were harvested. Markers involved in local invasion, distant metastasis and tumor-stroma interactions including miRs were compared between BT-474 and MDA-MB-231 cell lines and their xenografts by q-RT-PCR, immunofluorescence and immunohistochemistry.

Results: As expected BT-474 xenografts showed a higher rate of tumor growth when compared to MDA-MB-231. Histological examination of BT-474 tumors confirmed only locally invasive tumor growth with infiltrated blood capillaries and vessels; no macro and microscopic metastases were observed in the organs collected. On the contrary, MDA-MB-231 xenografts showed highly undifferentiated tumor growth and frank lung metastasis and extra-pulmonary tumor growth in one of the five mice injected despite slow rate of local growth. Expression of matrix metalloproteases – MMP-2 & 9 was more than 30 fold upregulated in MDA-MB-231 xenografts as compared to BT-474. Elevated level of E-cadherin was observed in BT-474 but was absent in MDA-MB-231.

The most interesting differences were seen in the levels of miRs and cell-surface integrins. High levels of miR-18a, miR-93 and miR-182 were observed in BT-474 implants when compared to MDA-MB-231 which had a much lower level of these miRs. On the contrary, higher levels of integrin β3, and β1 were observed in MDA-MB-231 tumors when compared to BT-474. Integrin β6 was absent in both. The reciprocal relationship between these markers is being examined and compared between locally invasive tumors and metastatic triple negative breast cancers from our case series of human specimens (N=250).

Conclusion: miRs and integrins known to be involved in invasion are differentially regulated in tumors that are locally invasive compared to ones with distant metastasis. The level of the key targets of these miRs as well as additional integrins is being examined. Understanding the epigenetic regulations leading to metastasis via tumor-stroma interaction might help in discerning differential tumor behaviour.

Citation Format: Lawrence PV, Desai K, Prabhu JS, Korlimarla A, Nair MG, Sridhar TS. Differential regulation of microRNAs and integrins influences metastatic potential: Comparison between locally invasive BT-474 and metastatic MDA-MB-231 xenografts [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-06-11.

Abstract P4-07-09: An approach to the identification of tumors driven by HER2 using the integrated activity of oncomiR miR-21 along with HER2 enriched genes

Introduction: The initial identification of HER2 as a driver in a subset of breast cancers was at the level of DNA (amplification), and subsequently noted at the level of transcripts and protein as well. However, the clinical selection of patients for treatment with Trastuzumab, has been through either IHC (protein) or FISH (DNA amplification) and not through transcript abundance. Interestingly, in most studies that have estimated transcript abundance in primary tumors, the proportion of patients that demonstrate increased transcript levels (termed HER2 Enriched) have tended to be slightly larger than the clinical HER2+ category.

A more clinically useful measure might be proof of HER2 downstream activity that might help separate tumors being driven significantly by HER2 from ones where its role is supportive. One of the many consequences of HER2 over-expression is activation of the oncomiR, miR-21 via the MAPK pathway. miR-21 in turn is known to epigenetically regulate multiple targets including the tumor suppressors PTEN and PDCD4. While these molecular mechanisms have been demonstrated convincingly in breast cancer cell lines, clinical studies of these alterations in large numbers are yet to be reported. In this study we have examined the relationship between clinical HER2 positivity and miR-21 levels in 124 surgically excised breast cancer specimens.

Methods: We selected 124 surgically excised specimens of primary breast cancers from our cohort that by HER2 immunohistochemistry (IHC) comprised 42 positive, 62 negative and 20 equivocal. Relative abundance of miR-21 was assessed using a TaqMan qRT-PCR, with normalization by RNU48. Relative transcript abundance of a set of 6 genes (HER2, GRB7, MLN64 and 3 reference genes) were evaluated by SYBR Green real time qPCR.

Results: The majority of tumors that were clinically HER2+ over expressed miR-21. A concordance with an AUC of 96% at 100% sensitivity and 85% specificity was noted. There is a highly significant differential expression of miR-21 between HER2 positive, negative and equivocal samples (P < 0.0001).

HER2 enriched score determined by using the expression levels of 3 genes (HER2, GRB7, MLN64) identified 35% (44/124) of the samples to be HER2 enriched. 72% of these (32/44) were also clinical HER2 positive by IHC. As expected, miR-21 was significantly over expressed in these tumors as well (P<0.0001).

To identify all samples which might show HER2 downstream activity, a logistic regression model was built using expression of miR-21, HER2, MLN64 and GRB7 as the determinants of HER2 status. The best fitting model classified 91% (38/42) of HER2 +, 95% (59/62) of the HER2 negative accurately with 94% specificity and an AUC of 0.96. The model helped identify 10% of clinical HER2 negative samples (6/20 equivocal & 3/62 HER-2 negative) to have a high probability of being HER2+.

Conclusion: Identification of HER2+ tumors with evidence of downstream activity may help identify patients with tumors being driven significantly by HER2 from ones where its role is supportive. The possibility of targeting miR-21 raises the tantalizing prospect of effecting change by altering the epigenetic regulation of multiple targets including tumor-suppressors.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-07-09.

Abstract P6-08-12: Gains in women’s education has not led to commensurate gains in seeking health-care early in breast cancer patients in urban India

Introduction:

Breast cancer is the leading cancer diagnosed in urban Indian women. Historically the proportion of women presenting with advanced disease has been in excess of 50% at most regional cancer centres. The past 20 years has witnessed rapid economic growth and urbanization with significant gains in women's education and access to health. However, it is not clear if this has translated to earlier seeking of care in the educated.

The aim of this study was to examine if higher education (College) was a determinant in the time of seeking first medical consultation, and whether there were significant differences between women under the age of 40 versus women over 60 years old at the time of diagnosis.

Methods:

The data for analysis were obtained from a prospective longitudinal observational study conducted between 2008-2013 at a medical teaching hospital and a tertiary specialized cancer care centre. A total of 460 patients have been enrolled so far. All patients provided informed consent and the study has been reviewed and approved by the institutional ethics committees at these institutions. We have collected from the patients and their medical records information about their age at diagnosis, educational level, stage of disease, histopathology reports and clinical details.

Results:

Data from 194 patients have been used for the analysis. Patients were divided into one group of < = 40Y of age (Group I, N = 58) and the second of > = 60 years of age (Group II, N = 136). Mean age at presentation for the groups was 35 and 68 years respectively. As expected almost 1.5 times as many women under the age of 40 (36%) were college educated compared to the women over 60 (22%) (p = 0.05). The proportion of LABC in the two groups was not different with group I having 27% and group II 25%. The proportion of older women with LABC and a college degree was 20%. However, rather than the expected decrease in proportion of women with high education and LABC, 31% of young women with LABC had a college degree. LABC in the college educated was not different in the group I when compared to group II. (p = 0.39).

Conclusion:

The determinants of seeking health care are complex and influenced by a variety of factors including socio-economic status, access to health care, education, cultural beliefs, and personal preferences. While urban India's steady economic growth has been highlighted by the scholarly as well as the lay press, the data presented here suggest that there is not an automatic and linear transfer between education, economics and healthcare seeking behaviours. We suggest that while a lot of attention has been paid to awareness and screening, we may need to focus on local cultural factors, and perhaps provide support from female counsellors and care providers as critical components of attempting to bring our women to the hospital at the earliest.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-08-12.

Evaluation of p53 and BCL2 expression, mutation, and aneuploidy status on treatment response in an Indian cohort of primary Ca larynx

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Background: Organ-sparing therapy consisting of cisplatin and 5-fluorouracil, combined with radiation for advanced head and neck squamous cell carcinoma (HNSCC) have been advocated in Ca larynx patients. However, failure of some tumors to respond to treatment or tumor recurrence limits the overall success of these therapies. P53 mutations have been linked to cisplatin resistance in other solid tumors. In this study we evaluate the relationships between P53 overexpression/mutations, BCL2 expression and ploidy status on treatment response in retrospective cohort of Ca Larynx patients. Methods: Samples from 18 patients with histopathologically confirmed Ca Larynx were analysed from our biorepository after consent. Clinical, sociodemographic information and response to treatment were abstracted from case records. P53 and BCL2 over expression were checked by IHC and p53 mutation by PCR and direct sequencing. DNA ploidy and S-phase fractions were also analysed. Bivariate relationships were determined between these variables using Spearmans rank correlation. Independent samples t tests were used to determine changes in P53 over expression, BCL2 expression Ploidy status and S phase fractions in both responders and non responders. Results: There was a trend for increase in P53 over expression and BCL2 expression and decrease in S phase fractions in responders vs non responders. Neither p53 over expression (75% of cases) and BCL2 over expression (17% of cases) correlated significantly with treatment response. However, BCL2 expression correlated negatively with disease stage (r = - 0.57, p = 0.02). Aneuploidy was observed in node positive tumors (p = 0.04). Conclusions: The results suggest poor association of molecular markers with treatment response and should not be relied as a marker for treatment response. Though there is a trend for association a larger sample size is required to demonstrate the findings.

No significant financial relationships to disclose.