Preliminary longitudinal evidence for stability of maternal behavior and infant stress regulation among infants born preterm at 4 and 9 months during the Still Face paradigm

Stress regulation begins to develop in the first year of life through interactions with caregivers, particularly in the presence of stressors. High quality caregiving, characterized by maternal sensitivity and responsiveness to the infant's emotional cues, is particularly important in the development of infant stress regulation. The purpose of this study was to assess the longitudinal stability of, and associations between, maternal interactive behavior and infant stress regulation (indexed by positive infant affect and cortisol reactivity) in response to the Still Face paradigm (SF) in a cohort of infants born preterm (< 32 weeks gestation, N = 22) at four months and nine months (adjusted age). The percent of time mothers spent using specific interaction styles (contingent maternal interaction (CMI), attention seeking, and watching) during Play/baseline, Reunion#1, and Reunion#2 SF episodes was calculated To assess infant stress regulation, two indices were obtained at both 4 and 9 months during the SF paradigm: the percent of positive affect displayed over each SF episode (0-100%) and a neuroendocrine stress response score based on salivary cortisol reactivity. We found three non-significant but medium-large effect size differences between 4 and 9 month variables, with more positive findings at 9 months. Regarding stability within the 4 month and 9 month episodes, maternal behavior and positive infant affect were non-significantly but moderately stable, with maternal watching behavior being particularly stable. Positive infant affect stability between Reunion#1 and Reunion#2 at 4 months was significantly greater than positive infant affect stability across these two episodes at 9 months. Regarding stability across 4 and 9 month (same) episodes, CMI and positive infant affect showed modest but non-significant stability across (same) 4 and 9 month episodes. Finally, with positive infant affect at Reunion#2 as the "outcome" of the Still Face, CMI at both 4 month Play and Reunion#1 episodes were significantly correlated with this "outcome." Further, positive infant affect at Reunion#2 was more strongly correlated with CMI at both Play and Reunion#1 for 4 month old compared with 9 month old infants. Thus, sensitive care appears particularly important for younger infants born preterm, and mothers' behavior early in a repeated stress exposure paradigm may be particularly important in maintaining positive infant affect and in the development of infants' stress regulation more generally. Identifying the longer-term effects of early stress on infant stress regulation, and its relationship with maternal interaction, has important implications for understanding trajectories of regulatory patterns and deficits. A greater understanding of these relationships is particularly important given that greater emotion and neuroendocrine stress regulation in infancy have been directly associated with numerous positive outcomes throughout childhood.

Pediatric Cancer Survivorship: Impact Upon Hair Cortisol Concentration and Family Functioning

A clearer understanding of the association between a biomarker of long-term stress reactivity and family functioning among pediatric cancer survivors may guide both survivorship research and clinical practice. The current study examined the relationship between a long-term measure of hypothalamic-pituitary-adrenal (HPA) activity (cortisol concentration; CORT_HAIR) and parent-reported family functioning (Family Environment Scale; FES) in a cross-sectional sample of survivors (n = 26) and controls (n = 53). Child CORT_HAIR was not different in survivors and controls, though treatment severity was significantly related to child survivor CORT_HAIR. Child CORT_HAIR and parent CORT_HAIR were positively correlated. Cancer survivor parents reported greater FES Organization. Child CORT_HAIR was inversely associated with FES Independence, while parent CORT_HAIR was inversely correlated with FES Organization. Parent CORT_HAIR and FES Independence were significant and unique predictors of child CORT_HAIR. Our results provide preliminary evidence for a relationship between a stress biomarker, child CORT_HAIR, and family functioning among pediatric cancer survivors and controls.

The role of maternal interactive behavior and gestational age in predicting infant affect during the Still-Face Paradigm

BACKGROUND

Emotion regulation develops through bidirectional affective communication.

AIM

To investigate the role of maternal interactive behavior in predicting infant affect among preterm versus full-term infants.

STUDY DESIGN

The association between maternal interactive behavior (contingent, attention seeking, watching) and infant affect during a modified Still Face (SF) paradigm in a sample of 22 preterm and 28 full term infants (3 ½ - 4 ½ months old) was investigated.

METHODS

Maternal behavior and infant affect were coded in one second intervals.

RESULTS

Maternal contingent interaction was positively correlated with positive infant affect (p < 0.001 for Play; p < 0.001 for Reunion#1; p < 0.01 for Reunion#2, respectively), with a stronger association during the second reunion for preterm infants (p < 0.001). In the preterm sample but not in the full-term sample, attention seeking maternal interaction at Play (baseline), Reunion#1, and Reunion#2 were all positively correlated with negative infant affect at Still Face#2. Maternal watching was negatively associated with positive infant affect for the full sample for both Reunion episodes (p < 0.05). Full term infants' negative affect increased from baseline to the first SF episode and then plateaued, whereas preterm infants demonstrated greater negative affect and less recovery throughout. Mothers of full-term infants showed increased contingent responding after the first SF stressor, while mothers of preterm infants did not (p < 0.05).

CONCLUSIONS

Preterm infants may be more susceptible to both positive and negative maternal behaviors and mothers of full-term infants may be more responsive to infants' increased distress. Relationship-focused interventions addressing maternal behaviors may enhance positive emotionality and improve self-regulation in medically at-risk infants.

Self-reported and parent proxy reported functional impairment among pediatric cancer survivors and controls

Background

A unique and limiting component in the research on functional impairment among children has been the exclusive use of parent proxy reports about child functioning; and there is limited information regarding the impact of pediatric cancer treatment on children’s day-to-day functioning and how this is related to neurocognitive functioning. The objective of the current study was to examine a novel measure of self-reported functional impairment, and explore the relationship between self-reported and parent-reported child functional impairment in pediatric cancer survivors compared to controls.

Methods

A cross-sectional cohort of survivors (n = 26) and controls (n = 53) were recruited. Survivors were off treatment an average of 6.35 years (SD = 5.38; range 1–15 years) and demonstrated an average “medium” Central Nervous System treatment intensity score. Participants completed measures of functional impairment (FI), intellectual assessment (RIST) and executive functions (NIH Examiner), while parents reported on children’s functional impairment.

Results

Survivors were similar to controls in functional impairment. Regardless of group membership, self-reported FI was higher than parent-reported FI, although they were correlated and parent report of FI significantly predicted self-reported FI. Across groups, increased impairment was associated with four of seven Examiner scores.

Conclusions

Research regarding self-reported functional impairment of cancer survivors and its association with parent-reported functional impairment and neurocognitive deficits has been limited. Our results suggest that self-reported FI appears to be a reasonable and viable outcome measure that corresponds with and adds incremental validity to parent reported FI. While low treatment intensity may confer relative sparing of functional impairment among survivors, children report higher FI levels than parents, suggesting that FI can be of clinical utility. In conclusion, pediatric cancer survivors should be screened for self-reported functional difficulties.

The association between maternal interaction and infant cortisol stress reactivity among preterm and full term infants at 4 months adjusted age

The purpose of this study was to assess the association between maternal interactive behavior and infant cortisol stress reactivity in response to the Still Face paradigm (SF) in a cohort of four-month old infants (adjusted age) born preterm (<32 weeks gestation, N = 22) compared with infants born full term (>37 weeks gestation, N = 28). Infant cortisol reactivity was calculated as area under the curve (AUC) from baseline to the third cortisol sample (30 min post-SF) using the trapezoidal rule, while the percent of time mothers spent using a contingent interaction style was measured (0-100%) during episodes 1 (Play; baseline), 3 (Reunion#1), and 5 (Reunion#2) while mother-infant dyads participated in the SF paradigm. We hypothesized that because infants born preterm are at increased risk for dysregulation, they would show, compared to full-term infants, a blunted stress response, involving under-responsiveness. We found blunted cortisol stress reactivity among the preterm infants. We also found that mothers of preterm infants demonstrated less contingent maternal interaction during Renion#1 of the SF; and that contingent maternal interaction at Reunion#2 of the SF was protective against cortisol stress reactivity in response to the SF. However, we did not find that the influence of maternal interaction on cortisol reactivity was moderated by gestational age group (full term vs preterm): the association between contingent maternal interaction and stress reactivity was similar for both gestational groups across episodes. In order to improve self-regulation and longer term social and cognitive developmental outcomes in medically at-risk infants, future research is warranted to determine how these findings relate to infants' stress reactions in naturalistic settings, and the directionality and temporal relationship between cortisol stress responses and maternal interactive behavior.

Abstract B33: Determination of protein expression of candidate prostate cancer genes from a novel region on chromosome 7 identified in African American men

In the United States, African American (AA) men are at 60% higher risk of developing prostate cancer than European American (EA) men, and AA men are 2.4 times more likely to die from prostate cancer than EA men. Although these disparities are frequently attributed to the greater aggressiveness of prostate cancer among AA men, it is not known what causes that prostate cancer aggressiveness in AA men. To identify germline genetic variation that could explain some of this disparity, our previous admixture mapping study identified a novel region on chromosome 7q31-34 where local ancestry was associated with risk of disease. The main objective of this study is to investigate whether candidate genes in this gene region show differences in protein product expression by cell line origin (AA vs. EA) and by cell line metastatic potential. We specifically examined the expression of three proteins sourced from this gene region through immunoblot analysis, filamin C (FLNC), glutamate receptor metabotropic B (GRM8), and cadherin-like and PC-esterase domain containing 1 (CPED1). The cell lines DU-145, PC3, LNCaP, RWPE1, and WPE1 were derived from biological specimens from EA men, whereas the PCa2b and the RC77T cell lines were sourced from AA men. The RWPE1 and WPE1 cell lines were derived from normal prostate cells, while the remaining cell lines were derived from metastatic prostate cancers. Using immunoblot analysis, we found that GRM8 is expressed at higher levels in the cell lines derived from AA men with prostate cancer compared to those from EA men with prostate cancer. In contrast, FLNC and CPED1 are expressed at higher levels in the cell lines from EA men with prostate cancer compared to those from AA men with prostate cancer. Interestingly, both FLNC and CPED1 expression is also low in the androgen sensitive LNCaP cell line. Importantly, these results are consistent with our fine mapping results in AA men, where the SNP with greatest evidence for association is located. Further, previous studies have demonstrated that the methylation status and mRNA expression of CPED1 and FLNC differed between prostate cancers from AA and EA men. Taken together, these results provide us with a foundation to test the relevance of these genes in prostate cancer growth and metastasis and contribute to our understanding of the molecular differences in prostate cancer between EA and AA men.

Citation Format: Casey Wizner, Julie Ruterbusch, Nicole Kubinec, Gregory Dyson, Albert Levin, Julie Boerner, Cathryn Bock. Determination of protein expression of candidate prostate cancer genes from a novel region on chromosome 7 identified in African American men. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B33.