Effects of oral iodine supplementation in very low birth weight preterm infants for the prevention of thyroid function alterations during the neonatal period: results of a randomised assessor-blinded pilot trial and neurodevelopmental outcomes at 24 months

The trace element iodine (I) is essential for the synthesis of thyroid hormones. Parenteral nutrition solutions, formula milk, and human breast milk contain insufficient iodine to meet recommended intake for preterm infants. Iodine deficiency may affect thyroid function and may be associated with morbidity or neurological outcomes. The primary objective is to assess the evidence that dietary supplementation with iodine affects thyroid function during the neonatal period. The design was a randomised controlled pilot trial. Infants who met the inclusion criteria were enrolled through consecutive sampling and assigned to two different groups. The setting was a Spanish university hospital. Ninety-four patients with very low birth weight (under 1500 g) were included. Intervention group: 30 µg I/kg/day of iodine in oral drops given to 47 infants from their first day of life until hospital discharge. Control group: 47 infants without supplements. Formula and maternal milk samples for the determination of iodine content were collected at 1, 7, 15, 21, 30 days, and at discharge. Blood samples were collected for thyroid hormones. Neurological development was assessed at 2 years of age (Bayley III Test). Infants in the supplemented group reached the recommended levels from the first days of life. The researchers detected the effects of iodine balance on the plasma levels of thyroid hormones measured during the first 12 weeks of age. The trial assessed the impact of the intervention on neurodevelopmental morbidity.Conclusion: Thyroid function is related to iodine intake in preterm infants. Therefore, supplements should be added if iodine intake is found to be inadequate. The analyses found no effects of iodine supplementation on the composite scores for Bayley-III assessments in all major domains. The study results indicate potentially important effects on language development related to low iodine excretion during the first 4 weeks of life What is Known: • Thyroid function is related to iodine intake in preterm infants. • Preterm babies on formula preparations and with exclusive parenteral nutrition are at high risk of iodine deficiency. What is New: • Iodine intake should be monitored during the neonatal period. • Iodine supplements should be added if iodine intake is found to be inadequate.

Abstract P5-13-32: Mucin 4 expression in high risk breast cancer: Predicting and overcoming resistance to immunotherapy

Background HER2-positive (+) and triple negative breast cancer (TNBC) have the worst survival among BC. BC patients are treated with chemotherapy (CT) and/or radiotherapy (RT), and HER2+ BC patients also receive targeted therapies, such as trastuzumab (Tz). The abundance of tumor infiltrating lymphocytes (TILs), in both HER2+ and TNBC, has a major good prognostic value. Thus, indicating that immunological evasion mechanisms are present in the tumor microenvironment (TME) hampering the efficacy of the treatments. We previously showed that soluble tumor necrosis factor α (sTNF) induces upregulation of mucin 4 (MUC4), which shields Tz epitope on HER2 impairing Tz binding and its effects. In preclinical models of de no5vo Tz-resistant tumors, administration of the sTNF blocking agent INB03 (DN) together with Tz inhibited tumor growth. We proved that MUC4 expression is an independent predictor of poor DFS in patients treated with adjuvant Tz. Our goal is to study whether MUC4 plays a role in tumor immune evasion in HER2+ and TNBC. Methods Untreated primary BC samples were assessed for TILs density (H&E) and MUC4 expression by immunohistochemistry. Tumors with TILs ≥30% and >50%, for TNBC and HER2+ BC respectively, and MUC4 scores 2 and 3 (0-3) were deemed positive. A cohort of 56 TNBC and 90 HER2+BC, stage I-III were retrospectively retrieved from Hospital Fernández and Instituto Henry Moore from 2013-2017, and clinicopathological and treatment characteristics were obtained from electronic records. TNBC were treated with adjuvant (41) or neoadjuvant CT +/- RT (15). HER2+BC patients received adjuvant Tz + CT. The association between MUC4 and OS was assessed by Kaplan Meier and log rank test and between MUC4 and TILs using Chi2. JIMT-1 HER2+ BC, de novo resistant tumors to Tz, containing a doxycycline (Dox)-inducible shRNA MUC4 plasmid (JIMT-1shMUC4) growing in nude mice were treated with IgG, Tz, DN or Tz + DN. Tumor growth was measured and macrophages and NK cells were determined in the TME by flow cytometry. Anti-asialo GM1 and clodronate-encapsulated liposomes were used to deplete NK cells and macrophages, respectively. Results We found an inverse relationship between TILs and MUC4 expression in HER2+ and TNBC (P=0.02 and P= 5 x10-5, respectively). Patients with MUC4+ TNBC have a shorter OS (P=0.03) and MUC4 was an independent predictor of OS [P=0.01; HR 4.9 (95%CI 1.4-17.0)]. To study MUC4 involvement in macrophage and NK cells recruitment in a Tz resistant model, nude mice bearing JIMT-1-shMUC4 tumors were treated or not with Dox to abolish MUC4 expression. Both groups received IgG, Tz, DN or DN + Tz. In control groups (without Dox), only Tz + DN administration was able to inhibit tumor growth (75% inhibition, P<0.0001 vs. IgG), in line with our previous results, and DN treatment reduced MUC4 expression. Knockdown of MUC4 expression by Dox, showed that Tz alone was effective in inhibiting JIMT-shMUC4 tumor growth at similar levels than Tz + DN group. Tumor growth inhibition was accompanied by an increase in NK cells activation and degranulation, and a rise in M1/M2 macrophage ratio. Depletion of macrophages or NK cells totally blunted antitumor effect of Tz + DN in control tumors. In MUC4-silenced tumors only macrophage depletion was able to abolish Tz antitumor effect. Conclusion Our results suggest that i) MUC4 expression is associated with immunologically “cold” HER2+ and TNBC, inducing an immunosuppressive TME that reflects in poor DFS/OS, and it confers resistance to Tz in HER2+ BC; ii) elimination of MUC4 expression reverses resistance to Tz; iii) tumor infiltrating macrophages are critical to the anti-tumor response in HER2+ BC. Patients with MUC4+ HER2+ or MUC4+ TNBC should benefit from sTNF blockade treatment leading to MUC4 downregulation and higher TILs, which would result in a better response to Tz and probably to immune checkpoint inhibitors.

Citation Format: Roxana Schillaci, Sofia Bruni, Florencia Mauro, María F Mercogliano, Agustina Roldan-Deamicis, Cecilia J Proietti, Rosalía Cordo-Russo, Gloria Inurrigarro, Agustina Dupont, Carla Adami, Daniel Lopez Della Vecchia, Sabrina Barchuck, Silvina Figurelli, Ernesto Gil Deza, Sandra Ares, Felipe G Gercovich, Patricia V Elizalde. Mucin 4 expression in high risk breast cancer: Predicting and overcoming resistance to immunotherapy [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-13-32.

SUN-122 Nuclear PDCD4 Expression Predicts Good Clinical Outcome in Luminal A-Like and Luminal B-Like Breast Cancer Subtypes

Hormone receptor-positive (HR+, estrogen and/or progesterone receptor-positive) and HER2-negative breast cancer (BC) subtype is a biologically heterogeneous entity that comprises 70% of BCs. This subtype includes both luminal (Lum) A- and B-like subtypes, which have differences in prognosis and sensitivity to endocrine therapies. The development of biomarkers guiding treatment decisions in these settings is required. Tumor suppressor PDCD4 (programmed cell death 4), which can be found both in the nucleus (NPDCD4) or the cytoplasm (CPDCD4), inhibits tumor growth and metastasis, and its loss is associated with poor prognosis in solid tumors. To explore the clinical relevance of PDCD4 in BC, we analyzed its expression by immunohistochemistry in a cohort of 619 patients with primary invasive BC. We found that 34.7% of patients showed NPDCD4 and 21.3% showed CPDCD4. NPDCD4 positivity, but not CPDCD4, was associated with lower clinical stage (P = 0.0003), with presence of more differentiated tumors (P = 6.4x10-6), and with estrogen and progesterone receptor (PR) expression (P = 9.2x10-9 and P = 2.8x10-9, respectively). Kaplan-Meier analysis revealed that NPDCD4 expression was associated with a longer overall survival (OS) and disease-free survival (DFS) in LumA-like (P = 0.008 and P = 0.028, respectively) and LumB-like (P = 0.004 and P = 0.012, respectively) subtypes. Interestingly, patients with LumB-like tumors displaying NPDCD4 presented estimated OS and DFS rates similar to the ones observed in patients with LumA-like tumors also expressing NPDCD4, indicating that its presence improves the clinical outcome of LumB-like patients. Multivariate Cox regression analysis identified NPDCD4 as an independent predictor of good clinical outcome in both LumA-like (HR: 0.45, 95% CI 0.22-0.96, P = 0.038) and LumB-like (HR: 0.28, 95% CI 0.10-0.80, P = 0.018) subtypes. We validated our results by in silico analysis using expression data from the METABRIC cohort. Bioinformatics analysis of BC cells from the Cancer Cell Line Encyclopedia revealed a positive correlation between PDCD4 and PR expression (P = 0.015). Since LumB-like tumors present a higher risk of resistance to endocrine therapy and both PR and PDCD4 levels in this subtype are lower than in the LumA-like one, we postulated that the presence of PR may modulate PDCD4 expression. Silencing of PR expression in HR+ cells decreased PDCD4 protein levels while reconstitution of PR in a PR-null cell line increased them, confirming PR requirement for PDCD4 modulation. In line with PDCD4 physiological function, its knockdown increased cell migration capability of HR+ BC cells, whereas its restoration led to a decrease in cell migration of HR-negative BC models. Our findings identified NPDCD4 positivity as a novel biomarker of clinical outcome in LumA- and B-like subtypes and revealed PDCD4 reconstitution as a novel therapeutic strategy in BC.

Invasive micropapillary carcinoma of the breast overexpresses MUC4 and is associated with poor outcome to adjuvant trastuzumab in HER2-positive breast cancer

Background

Invasive micropapillary carcinoma of the breast (IMPC) is a histological tumor variant that occurs with low frequency characterized by an inside-out formation of tumor clusters with a pseudopapillary arrangement. IMPC is an aggressive tumor with poor clinical outcome. In addition, this histological subtype usually expresses human epidermal growth factor receptor 2 (HER2) which also correlates with a more aggressive tumor. In this work we studied the clinical significance of IMPC in HER2-positive breast cancer patients treated with adjuvant trastuzumab. We also analyzed mucin 4 (MUC4) expression as a novel biomarker to identify IMPC.

Methods

We retrospectively studied 86 HER2-positive breast cancer patients treated with trastuzumab and chemotherapy in the adjuvant setting. We explored the association of the IMPC component with clinicopathological parameters at diagnosis and its prognostic value. We compared MUC4 expression in IMPC with respect to other histological breast cancer subtypes by immunohistochemistry.

Results

IMPC, either as a pure entity or associated with invasive ductal carcinoma (IDC), was present in 18.6% of HER2-positive cases. It was positively correlated with estrogen receptor expression and tumor size and inversely correlated with patient’s age. Disease-free survival was significantly lower in patients with IMPC (hazard ratio = 2.6; 95%, confidence interval 1.1–6.1, P = 0.0340). MUC4, a glycoprotein associated with metastasis, was strongly expressed in all IMPC cases tested. IMPC appeared as the histological breast cancer subtype with the highest MUC4 expression compared to IDC, lobular and mucinous carcinoma.

Conclusion

In HER2-positive breast cancer, the presence of IMPC should be carefully examined. As it is often not informed, because it is relatively difficult to identify or altogether overlooked, we propose MUC4 expression as a useful biomarker to highlight IMPC presence. Patients with MUC4-positive tumors with IMPC component should be more frequently monitored and/or receive additional therapies.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3897-x) contains supplementary material, which is available to authorized users.

TNFα-Induced Mucin 4 Expression Elicits Trastuzumab Resistance in HER2-Positive Breast Cancer

PURPOSE

Although trastuzumab administration improved the outcome of HER2-positive breast cancer patients, resistance events hamper its clinical benefits. We demonstrated that TNFα stimulation in vitro induces trastuzumab resistance in HER2-positive breast cancer cell lines. Here, we explored the mechanism of TNFα-induced trastuzumab resistance and the therapeutic strategies to overcome it.

EXPERIMENTAL DESIGN

Trastuzumab-sensitive breast cancer cells, genetically engineered to stably overexpress TNFα, and de novo trastuzumab-resistant tumors, were used to evaluate trastuzumab response and TNFα-blocking antibodies effectiveness respectively. Immunohistochemistry and antibody-dependent cell cytotoxicity (ADCC), together with siRNA strategy, were used to explore TNFα influence on the expression and function of its downstream target, mucin 4 (MUC4). The clinical relevance of MUC4 expression was studied in a cohort of 78 HER2-positive breast cancer patients treated with adjuvant trastuzumab.

RESULTS

TNFα overexpression turned trastuzumab-sensitive cells and tumors into resistant ones. Histopathologic findings revealed mucin foci in TNFα-producing tumors. TNFα induced upregulation of MUC4 that reduced trastuzumab binding to its epitope and impaired ADCC. Silencing MUC4 enhanced trastuzumab binding, increased ADCC, and overcame trastuzumab and trastuzumab-emtansine antiproliferative effects in TNFα-overexpressing cells. Accordingly, administration of TNFα-blocking antibodies downregulated MUC4 and sensitized de novo trastuzumab-resistant breast cancer cells and tumors to trastuzumab. In HER2-positive breast cancer samples, MUC4 expression was found to be an independent predictor of poor disease-free survival (P = 0.008).

CONCLUSIONS

We identified TNFα-induced MUC4 expression as a novel trastuzumab resistance mechanism. We propose MUC4 expression as a predictive biomarker of trastuzumab efficacy and a guide to combination therapy of TNFα-blocking antibodies with trastuzumab. Clin Cancer Res; 23(3); 636-48. ©2016 AACR.

Emotional and behavioral functioning among 10–14-year-old children who were very low birth weight at birth

Objective

This study examined the emotional and behavioral functioning among 10–14 year-old children who were born with very low birth weight (VLBW, <1500).

Method

Prospective and cross-sectional study of 90 VLBW (<1500 g) survivors born at the Hospital Universitario la Paz in Madrid, Spain, from 2000 to 2005 who were assessed by interviewers using the Strengths and Difficulties Questionnaire (SDQ). Parents also reported on their children's functioning. Children who showed an abnormal SDQ score on the total difficulties subscale or who had psychiatric history were also assessed using the K-SADS-PL.

Results

The proportion of children with abnormal-self-rated-SDQ scores was as follows: almost 25% of children showed an abnormal score on hyperactivity, nearly 15% on emotional problems, 15% on conduct problems and 10% on peer problems. Overall, 15% of children showed an abnormal score on the total difficulties subscale. Most children (99%) showed a normal score on the prosocial subscale. These proportions were higher when the questionnaire was rated by parents. Thirty-eight percent of children were assessed using the K-SADS and very few of them meet the criteria for at least one psychiatric disorder. Biomedical variables were associated in the expected direction to children's SDQ scores such as birth weight, head circumference and Apgar scores.

Conclusion

To conclude, being born with very low birth weight seems to be related to the emotional and behavioral functioning that these children appear to show between 10 and 15 years later.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Thyroid Hormones and the Psychomotor Development of the Newborn

Iodine is a trace element which is essential for the synthesis of thyroid hormones. If maternal iodine deficiency in pregnancy is severe, fetal brain damage will occur. This damage is irreversible after birth. Mild/moderate iodine deficiency during pregnancy and early postnatal life is associated with neuro/psycho-intellectual deficits in infants and children. The severity is not only related to the degree of iodine deficiency, but also to the developmental phase during which it is suffered, the most severe being the consequence of iodine deficiency during the first two trimesters of pregnancy. The close involvement between human brain development and thyroid hormones is widely accepted. The effects of T3 on the central nervous system are mediated by the regulation of the expression of genes that synthesize proteins implicated in cerebral neurogenesis, neuronal migration and differentiation, axonal outgrowth, dendritic ontogeny, and synaptogenesis. They are also necessary for cerebellar neurogenesis (predominantly during early postnatal life), gliogenesis (predominantly during late fetal life to 6 months postnatally), and myelogenesis (during the second trimester of gestation to 2 years of postnatal life). From clinical studies on the effect of iodine deficiency of both mother and fetus it becomes clear that T4 is required for brain development during gestation.

Low T4 levels during neonatal life could be a negative factor contributing to the neurodevelopmental problems of very preterm infants. Indeed, retrospective studies have shown a relationship between hypothyroxinemia and developmental delay and an increased risk of disabling cerebral palsy.

Distribution of bubble lengths in DNA

The distribution of bubble lengths in double-stranded DNA is presented for segments of varying guanine-cytosine (GC) content, obtained with Monte Carlo simulations using the Peyrard-Bishop-Dauxois model at 310 K. An analytical description of the obtained distribution in the whole regime investigated, i.e., up to bubble widths of the order of tens of nanometers, is available. We find that the decay lengths and characteristic exponents of this distribution show two distinct regimes as a function of GC content. The observed distribution is attributed to the anharmonic interactions within base pairs. The results are discussed in the framework of the Poland-Scheraga and the Peyrard-Bishop (with linear instead of nonlinear stacking interaction) models.

Bubble nucleation and cooperativity in DNA melting

The onset of intermediate states (denaturation bubbles) and their role during the melting transition of DNA are studied using the Peyrard-Bishop-Dauxois model by Monte Carlo simulations with no adjustable parameters. Comparison is made with previously published experimental results finding excellent agreement. Melting curves, critical DNA segment length for stability of bubbles, and the possibility of a two-state transition are studied.

Neonatal hypothyroxinemia: effects of iodine intake and premature birth

We have investigated the effects of iodine (I) intake on urinary I excretion in preterm (PT) babies up to 2 months after birth and its effect on serum T4, free T4 (FT4), T3, TSH, and thyroglobulin (Tg) levels compared to those in term (T) newborns. Very premature and very sick infants were in negative I balance for the first weeks after birth. Later, these same infants, as well as the other PT and T newborns, were in positive balance; 75- 80% of the ingested I was not accounted for in the urine. The urinary I levels of PT and T neonates cannot be equated to their I intakes. T4, FT4, and T3 levels in PT and T neonates increased with postmenstrual age, whereas Tg decreased and TSH did not change. Serum FT4, T3, Tg, and TSH levels in PT neonates were affected negatively, independently from age, by a low I intake. PT birth also affected T4, FT4, and Tg negatively, independently from I intake and postmenstrual age, for at least 6-8 weeks after birth. Care should be taken to avoid I deficiency in PT neonates. However, even when I intake is adequate, PT newborns are hypothyroxinemic compared to T babies during an important period of brain development. This suggests the possible convenience of interventions that might mimic the intrauterine hormone environment and accelerate maturation.

Thyroid gland volume as measured by ultrasonography in preterm infants

The volume of the thyroid gland was determined by ultrasonography in 30 preterm infants (27-36 weeks' gestation) born in Madrid. Thyroid gland volume significantly increased (p < 0.01) with postnatal and postmenstrual age and was very well correlated with body weight, height and surface area (p < 0.01). Serum thyroid hormones 3,5,3'-triiodothyronine (T3) and free thyroxine (FT4) were linearly correlated with postnatal and postmenstrual age, thus T3 and FT4 levels were also correlated with thyroid gland volume (p < 0.05). We report measurements of the thyroid gland volume obtained by ultrasonography in this group of preterm infants. Quantitative determination of thyroid gland volume is more accurate for the diagnosis of goitre than clinical criteria. It is also interesting to determine the thyroid gland volume in the neonatal period when the thyroid is particularly hypersensitive to the effects of iodine deficiency and excess.

Iodine content of infant formulas and iodine intake of premature babies: high risk of iodine deficiency

As part of a study of thyroid function in premature babies, the iodine content of their mothers' breast milk, that of 32 formulas from different brands used in Spain, and that of 127 formulas used in other countries was determined. Breast milk contained more iodine--mean (SEM) 10 (1) microgram/dl--than most of the formulas, especially those for premature babies. Iodine intakes were therefore below the recommended daily amount (RDA) for newborns: babies of 27-30 weeks' gestational age took 3.1 (1.1) micrograms/day at 5 days of age and 29.8 (2.7) micrograms by 2 months of age. This problem is not exclusive to Spanish premature babies as the iodine content of many of the formulas on sale in other countries was also inadequate. It is concluded that preterm infants who are formula fed are at high risk of iodine deficiency.