Intrauterine Inflammation, Excessive Fetal Growth and Respiratory Morbidities in Moderate-To-Late Preterm Neonates

INTRODUCTION

Respiratory morbidities in neonates are often progressive and life-threatening, and its early prediction is crucial. Intrauterine inflammation is one of the key control variables of respiratory morbidities in both very preterm and term neonates; however, little is known about its effects in the remaining group of moderate-to-late preterm neonates born between 32+0 and 36+6 weeks of gestation. This study aimed to confirm whether intrauterine inflammation is associated with respiratory morbidities in moderate-to-late preterm neonates.

METHODS

A single-center retrospective observational study was conducted in neonates born between 32+0 and 34+6 weeks of gestation between April 2013 and March 2018. The correlation between respiratory morbidities (defined as a requirement for invasive mechanical ventilation longer than the median duration of 3 days) and intrauterine inflammation was assessed using multivariable logistic regression analysis.

RESULTS

The study population comprised 242 neonates born at 33.7 ± 0.8 weeks of gestation and weighing 1,936 ± 381 g. The multivariable model to predict the outcome comprised respiratory distress syndrome (odds ratio [OR]: 9.1; 95% confidence interval [CI]: 3.7-22.5; p < 0.001), lower gestational age (per week; OR: 0.5; 95% CI: 0.3-0.8; p < 0.005), higher birth-weight z-score (OR: 1.6; 95% CI: 1.2-2.2; p < 0.005), lower cord blood pH (per 0.10; OR: 0.5; 95% CI: 0.3-0.7; p < 0.005), and chorioamnionitis (OR: 2.8; 95% CI: 1.1-7.2; p < 0.05).

CONCLUSION

Together with the incidence of respiratory distress syndrome and gestational age, chorioamnionitis and high birth-weight z-scores were associated with an increased incidence of respiratory morbidities in moderate-to-late preterm neonates. The deleterious impact of intrauterine inflammation on the lungs may be common in neonates of virtually all gestational ages. Traditional admission policy of neonatal intensive care units based on a threshold birth-weight, may leave a group of neonates without close observation despite their increased risks for respiratory morbidities.

Acquired hydrocephalus following hypoxic ischemic encephalopathy without intraventricular hemorrhage: A case report

The most common cause of acquired hydrocephalus in infants is hemorrhage, most often as a consequence of prematurity. Other important causes include neoplasm and infection, usually bacterial meningitis. Hypoxic ischemic encephalopathy (HIE) in term infants usually results in secondary microcephaly. We report an infant with severe HIE at birth treated by therapeutic hypothermia who developed progressive acquired hydrocephalus over 2 months, although no cause of the hydrocephalus was identified. Although hydrocephalus, even intraventricular hemorrhage, is uncommon in term infants with HIE, careful follow-up of the head circumference is important, even if no findings indicating possible causes of hydrocephalus, such as hemorrhage, are detected on ultrasound or magnetic resonance imaging.

Unusual presentation of acute encephalopathy with biphasic seizures and late reduced diffusion in Miller-Dieker syndrome

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a unique subtype of acute encephalopathy that occurs in children. A girl aged 2 years and 8 months with Miller-Dieker syndrome (MDS) was admitted for status epilepticus and high fever. Brain MRI performed on the third day postadmission showed abnormally high intensities in the subcortical white matter on diffusion-weighted images. Acute encephalitis/encephalopathy was diagnosed based on the electroencephalography (EEG) findings of diffuse high-voltage delta waves. Six days postadmission, frequent apnoeic episodes were observed, with oxygen desaturation due to cluster seizures. Subclinical seizures were found on amplitude-integrated EEG (aEEG). The disturbance of consciousness was difficult to recognise because of severe developmental disabilities due to MDS. EEG aids in the evaluation of consciousness, and aEEG can be helpful in monitoring and controlling subclinical seizures in the biphasic phase of AESD, especially in patients with underlying neurological disorders.

Congenital nephrogenic diabetes insipidus presenting as osmotic demyelination syndrome in infancy: A case report

RATIONALE

Almost 90% of congenital nephrogenic diabetes insipidus (NDI) cases are caused by mutations in the arginine vasopressin receptor 2 gene, which has X-linked recessive inheritance. Although NDI is commonly diagnosed in early infancy based on its characteristic findings, clinical diagnosis can be delayed when no other family members have been diagnosed with NDI because several findings of NDI are nonspecific.

PATIENT CONCERNS

A 3-month-old boy diagnosed with NDI presenting with osmotic demyelination syndrome (ODS) was admitted for poor weight gain after birth and poor feeding during the week prior to admission.

DIAGNOSIS

On admission, the initial blood examination showed hypernatremia (158 mmol/L), and treatment with intravenous fluids over the next 2 days further elevated the serum sodium level (171 mmol/L). After admission, polyuria was recognized, and polyuria in his grandmother and mother since childhood without a diagnosis of NDI was found. Magnetic resonance imaging showed multifocal, symmetrical lesions, including the lateral pons, on diffusion- and T2-weighted imaging, which led to a diagnosis of ODS.

INTERVENTION

The infusion was stopped, and the patient was fed milk diluted 2-fold with water.

OUTCOMES

The serum sodium level gradually decreased to 148 mmol/L over the course of 1 week. Low-sodium milk was started at 4 months of age and maintained a serum sodium level of approximately 140 mmol/L, which was within the normal range. The developmental quotient was 94 at 4 years of age.

LESSONS

ODS is an encephalopathy resulting from extreme fluctuations in serum sodium concentration and plasma osmolality. ODS due to hypernatremia has been reported in several patients, although it usually occurs during rapid correction of hyponatremia. Consequences of the central nervous system are a critical complication of NDI that affects prognosis. These consequences can be avoided with treatment. Early blood examination or polyuria in the patient, mother, or another family member and hypernatremic dehydration with good urine output should lead to an early diagnosis and prevent central nervous system consequences.

Dual-Task Training Combining Cognitive Tasks and Occupations among Japanese Community-Dwelling Older Adults: A Pilot Study

This study investigated whether dual tasks comprising cognitive tasks and occupations related to daily living can improve the mental and cognitive function of Japanese community-dwelling older adults. Participants included 30 older adults, equally divided into intervention and control groups. The outcome measures were memory, attention, depression, and health-related quality of life. No adverse effects of the intervention were observed in any participant in the intervention group. Logical memory I, logical memory II, and Center for Epidemiologic Studies Depression Scale scores showed a significant interaction. Dual tasks combining cognitive tasks and occupations may help improve delayed recall and alleviate depression. A novel attempt to integrate cognitive stimulation and activities valued by individuals may help mediate age-related cognitive function decline and reduce depressive symptoms in community-dwelling older adults.

Evidence of both foetal inflammation and hypoxia-ischaemia is associated with meconium aspiration syndrome

Foetal hypoxia–ischaemia is a key trigger of meconium aspiration syndrome (MAS). However, many neonates develop MAS without evidence of hypoxia–ischaemia, suggesting the presence of covert but important risk variables. We evaluated the association of MAS with clinical variables, placental histopathologic findings, and inflammatory biomarkers at birth. Of 1336 symptomatic and asymptomatic term singleton neonates with meconium-stained amniotic fluid, 88 neonates (6.6%) developed MAS. Univariate analysis showed that MAS development was associated with low 1- and 5-min Apgar scores, low cord blood pH, funisitis, higher α₁-acid glycoprotein levels, and higher haptoglobin levels (all p < 0.001 except for p = 0.001 for haptoglobin). Associations of MAS with caesarean delivery (p = 0.004), premature rupture of the membranes (p = 0.006), chorioamnionitis (p = 0.007), and higher C-reactive protein levels (p = 0.008) were lost when adjusted for multiple comparisons. The final multivariate model to explain MAS development comprised lower cord blood pH (odds ratio [OR] 0.58; 95% confidence interval [CI] 0.47–0.73; p < 0.001), funisitis (OR 2.45; 95% Cl 1.41–4.26; p = 0.002), and higher α₁-acid glycoprotein levels (OR 1.02; 95% Cl 1.01–1.03; p = 0.001). Our data from a large cohort of neonates suggested that intrauterine inflammation is one of the key independent variables of MAS development, together with foetal hypoxia–ischaemia.

Necrotizing Funisitis as an Intrauterine manifestation of Cryopyrin-Associated Periodic Syndrome: a case report and review of the literature

BACKGROUND

Cryopyrin-associated periodic syndrome (CAPS) is a life-long, autoinflammatory disease associated with a gain-of-function mutation in the nucleotide-binding domain, leucine-rich repeat family, pyrin domain containing 3 (NLRP3) gene, which result in uncontrolled production of IL-1β and chronic inflammation. Chronic infantile neurologic cutaneous and articular (CINCA) syndrome/neonatal-Onset multisystem inflammatory disease (NOMID) is the most severe form of CAPS. Although the first symptoms may be presented at birth, there are few reports on the involvement of the placenta and umbilical cord in the disease. Therefore, we present herein a preterm case of CINCA/NOMID syndrome and confirms intrauterine-onset inflammation with conclusive evidence by using fetal and placental histopathological examination.

CASE PRESENTATION

The female patient was born at 33weeks of gestation by emergency caesarean section and weighted at 1,514 g. The most common manifestations of CINCA/NOMID syndrome including recurrent fever, urticarial rash, and ventriculomegaly due to aseptic meningitis were presented. She also exhibited atypical symptoms such as severe hepatosplenomegaly with cholestasis. The genetic analysis of NLRP3 revealed a heterozygous c.1698 C > G (p.Phe566Leu) mutation, and she was diagnosed with CINCA/NOMID syndrome. Further, a histopathological examination revealed necrotizing funisitis, mainly inflammation of the umbilical artery, along with focal neutrophilic and lymphocytic villitis.

CONCLUSIONS

The necrotizing funisitis, which only involved the artery, was an unusual observation for chorioamnionitis. These evidences suggest that foetal inflammation, probably due to overproduction of IL-1β, caused tissue damage in utero, and the first symptom of a newborn with CINCA/NOMID.

Serial evaluation of cardiac allograft vasculopathy after heart transplantation by dual-modality intravascular ultrasound and optical coherence tomography

Background

Cardiac allograft vasculopathy is a combination of the development of de novo plaque and the progression of donor-transmitted plaque.

Purpose

This study aimed to evaluate the development of de novo plaque and the progression of donor-transmitted plaque within 12-month after heart transplantation (HTx) using serial intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The association between inflammatory cytokines and plaque progression was also examined.

Methods

We prospectively enrolled 40 recipients to conduct serial three-vessel IVUS and OCT analysis at 8-week and 12-month after HTx. De novo plaque was defined as having maximum intimal thickness (MIT) ≥0.5 mm at 12-month in the absence of donor-transmitted plaques (MIT ≥0.5 mm at 8-week). Serum cytokines were screened with a bead-based multiplex assay.

Results

A total of 13 de novo plaques (fibrous, n=10; fibroatheroma, n=3) were detected in eight recipients. Serum interleukin (IL)-31 at 8-week was associated with the development of de novo plaques (p=0.009). A total of 31 donor-transmitted plaques (fibrous, n=12; fibroatheroma, n=11; fibrocalcific, n=8) were detected in 17 recipients. Multiple regression analysis revealed that fibrous (p=0.026) and fibroatheroma (p=0.012) observed at 8-week were significantly associated with subsequent plaque progression within 12-month after HTx. ΔPlaque burden was significant higher in de novo plaque than donor-transmitted plaque (38.8% [29.6–41.2] versus 8.7% [1.3–13.6], p&lt;0.001). The prevalence of macrophage accumulation was lower in de novo plaque than in donor-transmitted plaque (8% versus 52%, p=0.006). Serum IL-31 at 8-week was correlated with the progression of donor-transmitted plaque as well as de novo plaque (r=0.663, p=0.029) although other cytokines like IL-1β, IL-6, IL-17, and tissue necrotic factor alpha were not.

Conclusions

In de novo plaques, fibrous plaque was the most common and macrophage accumulation was rarely observed. In donor-transmitted plaque, fibrous and fibroatheroma were independent predictor for the subsequent plaque progression. Serum interleukin-31 surge at subacute phase may play pathogenic role in cardiac allograft vasculopathy.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grants-in-Aid for Scientific Research (KAKENHI)

A severe case of Menkes disease with repeated bone fracture during the neonatal period, followed by multiple arterial occlusion

Menkes disease (MD) is a lethal infantile neurodegenerative disorder with X-linked inheritance, characterized by progressive neurodegenerative symptoms caused by pathogenic variants in the ATP7A. Early diagnosis and treatment are important, although the diagnosis is difficult prior to 2 months of age. We present an unusually severe case of MD with skull fractures at the birth and repeated fractures during the neonatal period, with further examinations leading to diagnosis. The patient died due to hemorrhagic shock, due to multiple arterial occlusion despite initiation of copper-histidine therapy in early infancy. Bone fracture at birth and multiple arterial occlusion are very rare findings in MD. This unusual and severe presentation emphasizes the importance of early diagnosis and treatment. A congenital bone fracture should be considered as a possible presentation of MD, especially in cases without birth complications.

Influence of foetal inflammation on the development of meconium aspiration syndrome in term neonates with meconium-stained amniotic fluid

Background

Meconium-stained amniotic fluid is observed in approximately 10–15% of all deliveries; however, only 5% of neonates with meconium-stained amniotic fluid develop meconium aspiration syndrome (MAS). Although foetal distress and subsequent sympathetic stimulation have been considered as the primary upstream events of MAS, this clinical complication sometimes occurs due to other pathologies, such as intraamniotic inflammation. The aim of this study was to investigate whether the incidence of MAS is associated with the presence of funisitis and chorioamnionitis in term neonates with meconium-stained amniotic fluid.

Methods

Between April 2013 and March 2015, a total of 95 term neonates with meconium-stained amniotic fluid, who were hospitalized at a neonatal intensive care unit, were enrolled in the study. The placenta and umbilical cord were histopathologically examined. Clinical variables and histopathological findings associated with the incidence of MAS were studied.

Results

A total of 36 neonates developed MAS. Univariate logistic regression analysis revealed that a heavier birth weight, male sex, 1-min Apgar score ≤ 7, funisitis (but not chorioamnionitis), and elevated acute-phase inflammatory reaction score were associated with increased incidence of MAS (all p < 0.05). The multivariate model comprised funisitis (OR = 5.03, 95% CI [1.63–15.5], 1-min Apgar score ≤ 7 (OR = 2.74, 95% CI [1.06–7.09], and male sex (OR = 3.4, 95% CI [1.24–9.34].

Conclusion

In neonates with meconium-stained amniotic fluid, funisitis, as well as low 1-min Apgar score and male sex, was identified as an independent variable for MAS development. Intraamniotic inflammation might be involved in the pathological mechanisms of MAS.

Progression-dependent transport heterogeneity of breast cancer liver metastases as a factor in therapeutic resistance

Metastatic disease is a major cause of mortality in cancer patients. While many drug delivery strategies for anticancer therapeutics have been developed in preclinical studies of primary tumors, the drug delivery properties of metastatic tumors have not been sufficiently investigated. Therapeutic efficacy hinges on efficient drug permeation into the tumor microenvironment, which is known to be heterogeneous thus potentially making drug permeation heterogeneous, also. In this study, we have identified that 4 T1 liver metastases, treated with pegylated liposomal doxorubicin, have unfavorable and heterogeneous transport of doxorubicin. Our drug extravasation results differ greatly from analogous studies with 4 T1 tumors growing in the primary site. A probabilistic tumor population model was developed to estimate drug permeation efficiency and drug kinetics of liver metastases by integrating the transport and structural properties of tumors and delivered drugs. The results demonstrate significant heterogeneity in metastases with regard to transport properties of doxorubicin within the same animal model, and even within the same organ. These results also suggest that the degree of heterogeneity depends on the stage of tumor progression and that differences in transport properties can define transport-based tumor phenotypes. These findings may have valuable clinical implications by illustrating that therapeutic agents can permeate and eliminate metastases of "less resistant" transport phenotypes, while sparing tumors with more "resistant" transport properties. We anticipate that these results could challenge the current paradigm of drug delivery into metastases, highlight potential caveats for therapies that may alter tumor perfusion, and deepen our understanding of the emergence of drug transport-based therapeutic resistance.

Prognostic factors of hydrops fetalis with pleural effusion

BACKGROUND

Hydrops fetalis (HF) has a low survival rate, particularly in the case of preterm birth. In addition, the severity index of HF has not been fully investigated yet. The aim of this study was to clarify the prognostic factors of HF with pleural effusion.

METHODS

All live-born HF patients with pleural effusion, except for chromosomal abnormality or complex congenital heart disease, born from 2009 to 2013 in Aichi Prefecture in Japan were included. Prenatal, perinatal, and postnatal information was obtained from the medical records and was retrospectively analyzed.

RESULTS

Forty-one HF patients with pleural effusion were included, and 28 patients (68%) survived. On multivariate logistic stepwise analysis, gestational birth week (OR, 0.71; 95% CI: 0.52-0.96, P = 0.027) and standard deviation (SD) score of the birthweight (OR, 1.74; 95% CI: 1.01-2.99, P = 0.045) were significant factors for postnatal death. All patients with both ≥32 gestational weeks and <3.0 birthweight SD score survived.

CONCLUSIONS

Combined with the gestational weeks data, birthweight SD score may be useful to estimate the prognosis of HF with pleural effusion.

Multicenter study for brain/body hypothermia for hypoxic-ischemic encephalopathy: Changes in HMGB-1

BACKGROUND

We measured changes in the blood level of high-mobility group box-1 (HMGB-1) at 24 h intervals in neonates treated with brain/body hypothermia (body hypothermia therapy: BHT) for hypoxic-ischemic encephalopathy (HIE), to evaluate the usefulness of HMGB-1 level for determining outcomes.

METHODS

We studied 15 neonates with HIE who underwent BHT (BHT (+) group) and six neonates with HIE who did not (BHT (-) group). We recorded HMGB-1 changes at 24 h intervals, creatinine phosphokinase, and the resistance index of the anterior cerebral artery. Magnetic resonance imaging (MRI) was used to determine short-term outcome.

RESULT

Baseline HMGB-1 was significantly higher in the BHT (+) group than in the BHT (-) group. Thereafter, HMGB-1 in the BHT (+) group significantly decreased at 24 h intervals, reaching the reference range by 2 days of age. In the BHT (+) group, when patients were classified into clinically significant neurological disorder due to HIE (+) and (-) according to MRI, the neurological disorder (+) group had higher mean HMGB-1.

CONCLUSIONS

In HIE, HMGB-1 differs according to the presence of BHT, suggesting that HMGB-1 measurement soon after birth might be useful for determining BHT necessity and short-term outcome.

Comprehensive molecular exploration identified promoter DNA methylation of the CRBP1 gene as a determinant of radiation sensitivity in rectal cancer

BACKGROUND

Neoadjuvant chemoradiotherapy (NCRT) for advanced rectal cancer (RC) is a well-evidenced therapy; however, some RC patients have no therapeutic response. Patient selection for NCRT so that non-responsive patients are excluded has been subjective. To date, no molecular markers indicating radiation sensitivity have been reported.

METHODS

We irradiated six colorectal cancer (CRC) cell lines and identified HCT116 cells as radiation-sensitive and HCT15 and DLD-1 cells as radiation resistant. Using a microarray, we selected candidate radiation sensitivity marker genes by choosing genes whose expression was consistent with a radiation-resistant or sensitive cell phenotype.

RESULTS

Among candidate genes, cellular retinol binding protein 1 (CRBP1) was of particular interest because it was not only induced in HCT116 cells by tentative 10 Gy radiation treatments, but also its expression was increased in HCT116-derived radiation-resistant cells vs parental cells. Forced expression of CRBP1 decreased the viability of both HCT15 and DLD-1 cells in response to radiation therapy. We also confirmed that CRBP1 was epigenetically silenced by hypermethylation of its promoter DNA, and that the quantitative methylation value of CRBP1 significantly correlated with histological response in RC patients with NCRT (P=0.031).

CONCLUSIONS

Our study identified CRBP1 as a radiation-sensitive predictor in RC.

The clinical significance of cysteine dioxygenase type 1 methylation in Barrett esophagus adenocarcinoma

Methylation of cysteine dioxygenase type 1 (CDO1) gene, a tumor suppressor gene, has been studied in various cancers; however, there is no information regarding Barrett esophagus cancer. In this study, the clinical significance of CDO1 methylation in Barrett esophagus adenocarcinoma (BEA) was clarified. CDO1 gene promoter methylation was analyzed for DNA from the patient's specimens using quantitative methylation-specific polymerase chain reaction. Thirty-eight BEA patients who underwent resection were identified between 2000 and 2014. Hypermethylation of CDO1 gene was demonstrated to be frequently recognized even at early stage in BEA by quantitative methylation-specific polymerase chain reaction. In BEA, there is a robust prognostic difference between stage I and stage II/III/IV with regard to 5-year relapse-free survival (P = 0.0016) and 5-year overall survival (P = 0.0024), and the tumor size separated by 7 cm was also a prognostic factor. There was significant difference in CDO1 gene methylation according to the tumor size (P = 0.036). BEA patients with CDO1 gene methylation were shown marginally significantly poorer prognosis (P = 0.054) than otherwise patients. In conclusion, higher CDO1 gene methylation was seen in BEA at earlier stage than in squamous cell carcinoma, and it may account for aggressive phenotype of BEA.

The question of whether or not to perform therapeutic hypothermia: A case of neonatal spinal cord injury

Neonatal spinal cord injury is an extremely rare perinatal complication that often occurs concurrently with hypoxic ischemic encephalopathy (HIE), further complicating diagnosis of spinal cord injury. Although therapeutic hypothermia for moderate to severe HIE is widely recommended in Japan, it is difficult to determine whether it satisfies the neurological findings-related entry criteria in some patients.We describe a female infant with neonatal spinal cord injury after forceps delivery, who underwent therapeutic hypothermia upon diagnosis of HIE. The Apgar scores were 5 at 1 min, 6 at 5 min, and not recorded at 10 min. Blood gas analysis of her umbilical artery was not performed. Since respiratory failure, hypotonia and the absence of primitive reflexes were found at 2 hours after birth, she was initially diagnosed with moderate HIE and underwent a therapeutic hypothermia. Magnetic resonance imaging after therapeutic hypothermia revealed the spinal cord was narrowed from the lower medulla oblongata to the upper cervical cord. Thus she was diagnosed with an upper spinal cord injury at that time.Some patients with neonatal spinal cord injuries satisfy the criteria for therapeutic hypothermia. When neonates with asphyxia present with prolonged respiratory failure and hypotonia, spinal cord injury should be considered in the differential diagnosis. Thus, an early MRI is vital for the diagnosis of spinal cord injury.

Robots in Human Environments: Basic Autonomous Capabilities

This article discusses the basic capabilities needed to enable robots to operate in human-populated environments for accomplishing both autonomous tasks and human-guided tasks. These capabilities are key to many new emerging robotic applications in service, construction, field, underwater, and space. An important characteristic of these robots is the “assistance” ability they can bring to humans in performing various physical tasks. To interact with humans and operate in their environments, these robots must be provided with the functionality of mobility and manipulation. The article presents developments of models, strategies, and algorithms concerned with a number of autonomous capabilities that are essential for robot operations in human environments. These capabilities include: integrated mobility and manipulation, cooperative skills between multiple robots, interaction ability with humans, and efficient techniques for real-time modification of collision-free path. These capabilities are demonstrated on two holonomic mobile platforms designed and built at Stanford University in collaboration with Oak Ridge National Laboratories and Nomadic Technologies.

Congenital rubella syndrome with death from interstitial pneumonia

There was a rubella epidemic in Japan in 2012-2013, which led to an increased number infants being born with congenital rubella syndrome (CRS). Symptoms of CRS are varied and include cataracts, congenital heart disease, and hearing impairment, but case reports of CRS complicated by interstitial pneumonia are rare. We report the case of a patient with CRS who died of respiratory failure caused by interstitial pneumonia. Thrombocytopenia had been present for approximately 1 month after birth, and the patient presented with sudden lung hemorrhage at 64 days old. Thereafter, respiratory condition deteriorated, and the patient died at 107 days old. Given that infants with CRS who have thrombocytopenia and interstitial pneumonia have a high risk of death, they should be monitored carefully for potential complications.

Abstract P3-06-07: Changes in the tumor microenvironment develop acquired resistance to pegylated liposomal doxorubicin in breast cancer mouse model

Pegylated liposomal doxorubicin (PLD) is one of the most widely used nanotherapeutics for the treatment of advanced/metastatic breast cancer. PLD accumulates in tumors utilizing so-called the enhanced permeation and retention (EPR) effect. Nevertheless, therapeutic efficacy and long term survival remain variable due to the development of acquired resistance. Elucidating the mechanisms of acquired resistance to PLD shall help developing new strategies to improve therapeutic outcome. It has been largely overlooked that the transport of therapeutics across biological barriers can significantly affect the efficacy of cancer therapies. Previously, we showed that the transport of PLD to tumors depends both on the tumor type and organ site. This effect is controlled by the extent to which endothelial cells (ECs) are covered by the collagen type IV (Col4) in the basement membrane, which in turn is influenced by the levels of MMP-9. Here, we have developed 4T1 tumor model which develops acquired resistance to PLD and spontaneous lung metastases. Our objective is to elucidate the resistant mechanism by evaluating the changes in the transport of PLD to the sensitive and resistant/metastatic tumors.

BALB/c mice bearing 4T1 cancers were treated with PLD intravenously when tumor volumes reached a size of approximately 100-200 mm3 . Tumor volumes in all mice decreased after initial PLD injections (sensitive). However, tumors started to grow again after 20 days and didn't respond to the second/third injections (resistant). Furthermore, 13 out of 14 mice developed spontaneous lung metastases. To elucidate the mechanisms of the resistance, mice bearing sensitive or resistant tumors were sacrificed after 24 hours of PLD injection, respectively. PLD accumulation in tumors was evaluated by imaging fluorescence of doxorubicin. Immunofluorescence staining was performed to evaluate the expression of ECs, Col4, MMP-9, and efflux pump associated p-glycoprotein (P-gp) in the primary tumors, and the expression of ECs and Col4 were also evaluated in lung metastases.

PLD accumulation was significantly decreased in the resistant tumors compared to the sensitive tumors, although P-gp expression was not increased in the resistant tumors. The amount of ECs and Col4 increased in the resistant tumors. Interestingly, ECs were covered more tightly by Col4 in the resistant tumors as compared with the sensitive tumors, which could decrease the EPR effect in the tumors. MMP-9 expression decreased in the resistant tumors, suggesting less degradation of Col4 in the basement membrane. Coverage of ECs by Col4 was similar between the metastatic lung tumors and uninvolved lung tissue as well as the resistant primary tumors, indicating the EPR effect is not increased in the metastatic tumors.

In summary, ratio of ECs covered by Col4 is higher in the resistant/metastatic tumors as compared to that in the sensitive primary tumors. This structural change in the tumor microenvironment, impeding the sufficient PLD transport to the tumors after the initial PLD therapy, can be a cause of acquired resistance/development of lung metastasis. These changes should be taken into account to develop strategies for overcoming the acquired resistance and metastasis.

Citation Format: Kai M, Liu YT, Saito Y, Ferrari M, Yokoi K. Changes in the tumor microenvironment develop acquired resistance to pegylated liposomal doxorubicin in breast cancer mouse model. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-06-07.

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Proposals for the Revision of the Clinical and Pathologic Staging of Small Cell Lung Cancer in the Forthcoming Eighth Edition of the TNM Classification for Lung Cancer

INTRODUCTION

Small cell lung cancer (SCLC) is commonly classified as either limited or extensive, but the Union for International Cancer Control TNM Classification of Malignant Tumours seventh edition (2009) recommended tumor, node, and metastasis (TNM) staging based on analysis of the International Association for the Study of Lung Cancer (IASLC) database.

METHODS

Survival analyses were performed for clinically and pathologically staged patients presenting with SCLC from 1999 through 2010. Prognosis was compared in relation to the TNM seventh edition staging to serve as validation and analyzed in relation to proposed changes to the T descriptors found in the eighth edition.

RESULTS

There were 5002 patients: 4848 patients with clinical and 582 with pathological stages. Among these, 428 had both. Survival differences were confirmed for T and N categories and maintained in relation to proposed revisions to T descriptors for seventh edition TNM categories and proposed changes in the eighth edition. There were also survival differences, notably at 12 months, in patients with brain-only single-site metastasis (SSM) compared to SSM at other sites, and SSM without a pleural effusion showed a better prognosis than other patients in the M1b category.

CONCLUSION

We confirm the prognostic value of clinical and pathological TNM staging in patients with SCLC, and recommend continued usage for SCLC in relation to proposed changes to T, N, and M descriptors for NSCLC in the eighth edition. However, for M descriptors, it remains uncertain whether survival differences in patients with SSM in the brain simply reflect better treatment options rather than better survival based on anatomic extent of disease.

Abstract P6-04-21: Novel therapy of liver metastases of cancer using abraxane loaded into multi-stage nanovector

Purpose; To investigate whether the Abraxane loaded within Multi-Stage Nanovector (MSV) system (MSV-ABX) is more effective in therapy of liver metastases of breast and lung cancer as compared to Abraxane (ABX).

Experimental Design; MTT assay was performed to evaluate sensitivity of 4T1, murine breast cancer cells and 3LL, murine lung cancer cells to ABX or MSV-ABX in vitro. Experimental liver metastases were produced by intra-splenic injection of 4T1 or 3LL cells in Balb/C mice. The mice bearing liver metastases were treated with intravenous injection of (1) control (PBS), (2) ABX or (3) MSV-ABX. Then the mice were sacrificed and liver weight was measured to evaluate the therapeutic efficacy. To evaluate the biological the effects of therapeutics, we performed histological and immunohistochemical analysis of the tumor specimens. Apoptosis of 4T1 and 3LL tumor cells were evaluated by TUNEL staining, and proliferation of the tumor cells were stained using antibody to Ki67. Tumor diameter was measured in H&E stained sections.

Results; There was no significant difference in the sensitivity of 4T1 and 3LL cancer cells to ABX and MSV-ABX, in vitro. All the mice injected with 4T1 or C3LL cells developed multiple liver metastases. The liver weight was significantly lower in the mice treated with MSV-ABX as compared to those in the other groups. The tumor diameters in the liver were significantly smaller in the mice treated with MSV-ABX as compared to those in the other two groups. Immunofluorescent analysis revealed that MSV-ABX inhibited proliferation and increased apoptosis of 4T1 and 3LL tumor cells in the liver significantly more than ABX.Conclusions; These studies demonstrate that MSV-ABX is more effective than ABX in therapy of the liver metastasis of breast and colorectal cancer in our mouse models. These data can be translated into the clinic for planning novel clinical trials using MSV-ABX.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-04-21.

Abstract P4-06-13: Discovering serum biomarkers for predicting accumulation of nanotherapeutics to different tumor and organ microenvironments

Surrogate biomarkers in the circulation for the enhanced permeation and retention (EPR) effect in different tumor and organ microenvironment shall aid in selecting patients who are likely to accumulate higher amount of nanotherapeutics to tumors and thus show better response to the therapeutics. In this study, 4T1 and 3LL murine cancer cell lines, known to have similar sensitivity to pegylated liposomal doxorubicin (PLD) in vitro, were shown to accumulate significantly different quantities of PLD in vivo. PLD accumulation correlated with tumor-specific differences in therapeutic efficacy and vascular permeability, which was modulated by the extent of coverage of tumor-associated endothelial cells by basement membrane. Matrix metalloproteinase (MMP)-9 and its endogenous inhibitor, tissue inhibitor of metalloproteinase (TIMP)-1, played a pivotal role in these phenomena. Differences in vascular permeability and PLD accumulation were also organ-specific and significantly correlated with the relative ratio of MMP-9 and TIMP-1 in the systemic circulation of the tumor-bearing mice. Our findings support the further development of MMP-9 and TIMP-1 as paired serum biomarkers for predicting accumulation of PLD to tumor and the application of these biomarkers could be expanded to other types of nanotherapeutics utilizing the EPR effect for the personalization of cancer therapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-06-13.

Time to first cigarette and lung cancer risk in Japan

BACKGROUND

Cigarette smoking is the major cause of lung cancer (LC). Although the time to first cigarette (TTFC) of the day is a distinct indicator of nicotine dependence, little information is available on its possible relation to LC.

PATIENTS AND METHODS

This case-control study includes a total of 1572 incident LC cases and 1572 non-cancer controls visiting for the first time the Aichi Cancer Center Hospital between 2001 and 2005. We estimated the odds ratio (OR) and 95% confidence interval (CI) for TTFC using a logistic regression model after adjustment for several potential confounders.

RESULTS

TTFC was inversely associated with the risk of LC. This association was consistent across histological subtypes of LC. For all LCs considered among ever smokers and after accurate allowance for smoking quantity and duration, besides other relevant covariates, compared with TTFC >60 min, the adjusted ORs were 1.08 (95% CI, 0.73-1.61) for TTFC of 31-60 min, 1.40 (0.98-2.01) for 6-30 min and 1.86 (1.28-2.71) for within 5 min (Ptrend, < 0.001). Statistically marginally significant heterogeneity by histological subtype was observed (Pheterogeneity, 0.002).

CONCLUSIONS

Nicotine dependence, as indicated by the TTFC, is associated with increased risk of LC and is therefore an independent marker of exposure to tobacco smoking.