Real-Time Tracking of Laryngeal Motion via the Surface Depth-Sensing Technique for Radiotherapy in Laryngeal Cancer Patients

Radiotherapy (RT) is an important modality for laryngeal cancer treatment to preserve laryngeal function. During beam delivery, laryngeal motion remains uncontrollable and may compromise tumor-targeting efficacy. We aimed to examine real-time laryngeal motion by developing a surface depth-sensing technique with preliminary testing during RT-based treatment of patients with laryngeal cancer. A surface depth-sensing (SDS) camera was set up and integrated into RT simulation procedures. By recording the natural swallowing of patients, SDS calculation was performed using the Pose Estimation Model and deep neural network technique. Seven male patients with laryngeal cancer were enrolled in this prospective study. The calculated motion distances of the laryngeal prominence (mean ± standard deviation) were 1.6 ± 0.8 mm, 21.4 ± 5.1 mm, 6.4 ± 3.3 mm, and 22.7 ± 4.9 mm in the left-right, cranio-caudal, and anterior-posterior directions and for the spatial displacement, respectively. The calculated differences in the 3D margins for generating the planning tumor volume by senior physicians with and without SDS data were -0.7 ± 1.0 mm (-18%), 11.3 ± 6.8 mm (235%), and 1.8 ± 2.6 mm (45%) in the left-right, cranio-caudal, and anterior-posterior directions, respectively. The SDS technique developed for detecting laryngeal motion during swallowing may be a practical guide for individualized RT design in the treatment of laryngeal cancer.

Epigenetic Modulation of Opioid Receptors by Drugs of Abuse

Chronic exposure to drugs of abuse produces profound changes in gene expression and neural activity associated with drug-seeking and taking behavior. Dysregulation of opioid receptor gene expression is commonly observed across a variety of abused substances including opioids, cocaine, and alcohol. Early studies in cultured cells showed that the spatial and temporal gene expression of opioid receptors are regulated by epigenetic mechanisms including DNA and histone modifications and non-coding RNAs. Accumulating evidence indicate that drugs of abuse can modulate opioid receptor gene expression by targeting various epigenetic regulatory networks. Based on current cellular and animal models of substance use disorder and clinical evidence, this review summarizes how chronic drug exposure alters the gene expression of mu, delta, kappa, and nociceptin receptors via DNA and histone modifications. The influence of drugs of abuse on epigenetic modulators, such as non-coding RNAs and transcription factors, is also presented. Finally, the therapeutic potential of manipulating epigenetic processes as an avenue to treat substance use disorder is discussed.

The Catalytic-Dependent and -Independent Roles of Lsd1 and Lsd2 Lysine Demethylases in Heterochromatin Formation in Schizosaccharomyces pombe

In eukaryotes, heterochromatin plays a critical role in organismal development and cell fate acquisition, through regulating gene expression. The evolutionarily conserved lysine-specific demethylases, Lsd1 and Lsd2, remove mono- and dimethylation on histone H3, serving complex roles in gene expression. In the fission yeast Schizosaccharomyces pombe, null mutations of Lsd1 and Lsd2 result in either severe growth defects or inviability, while catalytic inactivation causes minimal defects, indicating that Lsd1 and Lsd2 have essential functions beyond their known demethylase activity. Here, we show that catalytic mutants of Lsd1 or Lsd2 partially assemble functional heterochromatin at centromeres in RNAi-deficient cells, while the C-terminal truncated alleles of Lsd1 or Lsd2 exacerbate heterochromatin formation at all major heterochromatic regions, suggesting that Lsd1 and Lsd2 repress heterochromatic transcripts through mechanisms both dependent on and independent of their catalytic activities. Lsd1 and Lsd2 are also involved in the establishment and maintenance of heterochromatin. At constitutive heterochromatic regions, Lsd1 and Lsd2 regulate one another and cooperate with other histone modifiers, including the class II HDAC Clr3 and the Sirtuin family protein Sir2 for gene silencing, but not with the class I HDAC Clr6. Our findings explore the roles of lysine-specific demethylases in epigenetic gene silencing at heterochromatic regions.

Over expression of CDK4 and MDM2 in a patient with recurrent ALK-negative mediastinal inflammatory myofibroblastic tumor: A case report

RATIONALE

The diagnosis of anaplastic lymphoma kinase (ALK)-negative inflammatory myofibroblastic tumors (IMT) remains challenging because of their morphological resemblance with spindle cell sarcoma with myofibroblastic characteristics.

PATIENT CONCERNS

A 69-year-old female patient presented with loco-regional recurrent IMT several times within 8 years after primary treatment and neck lymph node metastasis 3.5 years after last recurrence.

DIAGNOSIS

The primary, recurrence, and lymph node metastasis lesions were diagnosed as ALK-negative IMTs based on the histopathological features.

INTERVENTIONS

Biopsy samples were obtained during repeated surgeries and evaluated for genomic alterations during first and recurrent presentations. The evaluation was done using pathway-driven massive parallel sequencing, and genomic alterations between primary and recurrent tumors were compared.

OUTCOMES

Copy number gains and overexpression of mouse double minute 2 homolog (MDM2) and cyclin dependent kinase 4 (CDK4) were observed in the primary lesion, and additional gene amplification of Discoidin Domain Receptor Tyrosine Kinase 2 (DDR2), Succinate Dehydrogenase Complex II subunit C (SDHC), and thyroid stimulating hormone receptor (TSHR) Q720H were found in the recurrent tumors. Metastases to the neck lymph node were observed 3.5 years after recurrence.

LESSONS

Our results indicated genetic evolution in a microscopically benign condition and highlighted the importance of molecular characterization of fibro-inflammatory lesions of uncertain malignant potential.

Bio-physic constraint model using spatial registration of delta 18F-fluorodeoxyglucose positron emission tomography/computed tomography images for predicting radiation pneumonitis in esophageal squamous cell carcinoma patients receiving neoadjuvant chemoradiation

PURPOSE

This study integrated clinical outcomes and radiomics of advanced thoracic esophageal squamous cell carcinoma patients receiving neoadjuvant concurrent chemoradiotherapy (NACCRT) to establish a novel constraint model for predicting radiation pneumonitis (RP).

PATIENTS AND METHODS

We conducted a retrospective review for thoracic advanced esophageal cancer patients who received NACCRT. From 2013 to 2018, 89 patients were eligible for review. Staging workup and response evaluation included positron emission tomography/computed tomography (PET/CT) scans and endoscopic ultrasound. Patients received RT with 48 Gy to gross tumor and 43.2 Gy to elective nodal area in simultaneous integrated boost method divided in 24 fractions. Weekly platinum-based chemotherapy was administered concurrently. Side effects were evaluated using CTCAE v4. Images of 2-fluoro-2-deoxyglucose PET/CT before and after NACCRT were registered to planning CT images to create a region of interest for dosimetry parameters that spatially matched RP-related regions, including V10, V20, V50%, V27, and V30. Correlation between bio-physic parameters and toxicity was used to establish a constraint model for avoiding RP.

RESULTS

Among the investigated cohort, clinical downstaging, complete pathological response, and 5-year overall survival rates were 59.6%, 40%, and 34.4%, respectively. Multivariate logistic regression analysis demonstrated that each individual set standardized uptake value ratios (SUVRs), neither pre- nor post-NACCRT, was not predictive. Interestingly, cutoff increments of 6.2% and 8.9% in SUVRs (delta-SUVR) in registered V20 and V27 regions were powerful predictors for acute and chronic RP, respectively.

CONCLUSION

Spatial registration of metabolic and planning CT images with delta-radiomics analysis using fore-and-aft image sets can establish a unique bio-physic prediction model for avoiding RP in esophageal cancer patients receiving NACCRT.

Folic acid inhibits endothelial cell migration through inhibiting the RhoA activity mediated by activating the folic acid receptor/cSrc/p190RhoGAP-signaling pathway

Previously, our in vivo studies demonstrated that folic acid (FA) could inhibit angiogenesis and in vitro studies showed that FA reduced vascular endothelial cell proliferation through activating the cSrc/ERK-2/NFκB/p53 pathway mediated by FA receptor (FR). Here, we further examined the effect of FA on endothelial cell migration. Our results showed that FA (10 μM) inhibited the formation of lamellipodia, migration and capillary-like tube formation of human umbilical venous endothelial cells (HUVEC). These inhibition effects induced by FA treatment were not due to reduction of cell survival and cell adhesion on the collagen-coated plate. Treatment of HUVEC with FA (10 μM) increased the activity of cSrc and p190RhoGAP and decreased the activity of RhoA. Over-expression of the constitutively active RhoA construct (RhoA V14) prevented the FA-induced inhibition of migration and capillary-like tube formation in HUVEC. However, these preventive effects were abolished by pretreatment of HUVEC with a ROCK inhibitor, Y27632. Pretreatment with a cSrc inhibitor, PP2, prevented the FA-induced activation of p190GAP, reduction of the RhoA activity and migration inhibition in HUVEC. Moreover, pre-transfection with p190RhoGAP siRNA abolished the FA-induced reduction in the RhoA activity and migration inhibition in HUVEC. Taken together, our results suggest that FA might inhibit endothelial cell migration through inhibiting the RhoA activity mediated by activating the FR/cSrc/p190RhoGAP-signaling pathway. These findings further support the anti-angiogenic activity of FA.

[Laboratory evaluation of automated enzyme linked fluorescent assay for detecting serum specific IgG antibodies against rubella virus]

The VIDAS rubella IgG(RBG) is a new, automated, enzyme-linkad fluorescent assay(ELFA) for detecting IgG antibodies to rubella virus in serum. The purpose of this study was to evaluate the usefulness of the qualitative and quantitative VIDAS RBG as laboratory tests in the rapid detecting anti-rubella IgG antibodies. Simultaneous parallel testing was performed by using the qualitative and quantitative RBG along with RUBAZYME(ABBOTT LABORATORIES) and the standard hemagglutination-inhibition(HI) test(R-HI kit, SEIKEN) on 200 blood samples submitted for anti-rubella IgG antibodies testing from patients at the VGH-Kaohsiung(Mar.-Sep., 1993). The qualitative and quantitative VIDAS RBG and RUBAZYME assay were compared to the standard R-HI test. Significant differences among the sensitivities of these three methods were found (100% sensitivity for the qualitative VIDAS RBG, 88.89% for the quantitative VIDAS RBG and 97.67% for the RUBAZYME). However, the specificities of these three methods were all the same, 100%. With these results we can conclude that the qualitative VIDAS RBG will provide a very good, precise and reliable method to determine serum specific IgG antibodies against rubella virus. Furthermore, the VIDAS RBG is fully automated and time-saving procedures (for every batch of test, it takes 25 minutes with VIDAS RBG, 2.5 hours with RUBAZYME and 4.5 hours with R-HI) in clinical laboratories.