Background: Cardiac development is a dynamic process both temporally and spatially. These complex processes are often disturbed and lead to congenital cardiac anomalies that affect approximately 1% of live births. Disease-causing variants in several genetic loci lead to cardiac anomalies, with variants in transcription factor NKX2-5 gene being one of the largest variants known. Gestational hypoxia, such as seen in high-altitude pregnancy, has been known to affect cardiac development, yet the incidence and underlying mechanisms are largely unknown.Methods and Results: Normal wild-type female mice mated with heterozygous Nkx2-5 mutant males were housed under moderate hypoxia (14% O2) or normoxia (20.9% O2) conditions from 10.5 days of gestation. Wild-type mice exposed to hypoxia demonstrate excessive trabeculation, ventricular septal defects, irregular morphology of interventricular septum as well as atrial septal abnormalities, which overlap with those seen in heterozygous Nkx2-5 mutant mice. Genome-wide transcriptome done by RNA-seq of a 2-day hypoxic exposure on wild-type embryos revealed abnormal transcriptomes, in which approximately 60% share those from Nkx2-5 mutants without hypoxia. Gestational hypoxia reduced the expression of Nkx2-5 proteins in more than one-half along with a reduction in phosphorylation, suggesting that abnormal Nkx2-5 function is a common mechanism shared between genetic and gestational hypoxia-induced cardiac anomalies, at least at a specific developing stage.Conclusion: The results of our study provide insights into a common molecular mechanism underlying non-genetic and genetic cardiac anomalies.

Cardiac development is a dynamic process, temporally and spatially. When disturbed, it leads to congenital cardiac anomalies that affect approximately 1% of live births. Genetic variants in several loci lead to anomalies, with the transcription factor NKX2-5 being one of the largest. However, there are also non-genetic factors that influence cardiac malformations. We examined the hypothesis that hyperoxia may be beneficial and can rescue genetic cardiac anomalies induced by an Nkx2-5 mutation. Intermittent mild hyperoxia (40% PO2) was applied for 10 h per day to normal wild-type female mice mated with heterozygous Nkx2-5 mutant males from gestational day 8.5 to birth. Hyperoxia therapy reduced excessive trabeculation in Nkx2-5 mutant mice compared to normoxic conditions (ratio of trabecular layer relative to compact layer area, normoxia 1.84 ± 0.07 vs. hyperoxia 1.51 ± 0.04) and frequency of muscular ventricular septal defects per heart (1.53 ± 0.32 vs. 0.68 ± 0.15); however, the incidence of membranous ventricular septal defects in Nkx2-5 mutant hearts was not changed. Nkx2-5 mutant embryonic hearts showed defective coronary vessel organization, which was improved by intermittent mild hyperoxia. The results of our study showed that mild gestational hyperoxia therapy rescued genetic cardiac malformation induced by Nkx2-5 mutation in part.

Background and Objectives: Sarcoma local recurrence (LR) is often associated with metastasis, but it is unclear if LR can be a causal event leading to metastasis. We question if LR is best viewed as an independent oncologic event or as a worrisome harbinger threatening a patient's overall survival. Methods:We identified patients with LR and/or metastasis from an ongoing cohort of 629 patients with primary sarcoma and performed a detailed review to assess the timing of metastasis resulting in the following groups: (1) Isolated LR, (2) LR before metastasis, (3) LR within 6 months of metastasis, (4) LR 6-12 months after metastasis, (5) LR >12 months after metastasis, and (6) metastasis at diagnosis.Results: Overall, 43 patients met the inclusion criteria with an LR rate of 7%. Ten patients (2% of the entire cohort, 23% of LR) developed an LR before or within 6 months of metastasis. For patients without systemic disease preceding LR, 3 of 23 soft tissue sarcoma STS (13%) and 7 of 10 bone sarcoma (70%) subsequently developed metastasis (p < 0.01). Conclusion:LR with subsequent metastasis is a rare event. LR appears to be best viewed as a marker of tumor aggressiveness rather than the cause of metastasis and poor survival. LR in bone sarcoma patients should warn providers of a high risk of imminent metastasis.

Background and Objectives: Nonpulmonary metastases (NPM) are rare, associated with a poorer prognosis, and maybe missed on conventional chest imaging for sarcoma surveillance. We determined (1) the proportion of NPM occurring in isolation or with synchronous or prior pulmonary metastases (PM), and (2) if initial NPM would have been recognized with a standard surveillance protocol.Methods: Investigators identified patients who developed initial NPM without prior evidence of or concurrent PM from an ongoing cohort of bone and soft tissue sarcoma (STS) patients. Logistic regression at univariate level was done.Results: There were 138/630 (22%) patients with metastasis and 66 (10%) had NPM: 50 (8%) patients had PM presenting first, while 16 (3%) had initial NPM.Malignant peripheral nerve sheath tumor, angiosarcoma, rhabdomyosarcoma, synovial sarcoma, and myxoid liposarcoma were six times more likely to develop initial NPM than other subtypes of STS with odds ratio = 6 (95% confidence interval:1.93-18.65, p value < 0.01). Chest imaging and physical examination were sufficient to identify NPM in all except three bone sarcoma patients.Conclusions: Patients who develop initial NPM are rare and demonstrate a predilection towards some subtypes of extremity sarcoma. They develop oligometastatic disease, which may be amenable for surgical excision. All isolated or initial NPM in STS patients were discovered by physical examination and standard chest imaging.