Abstract B26: Combinational effect of sulforaphane (SFN) and epigenetic demethylation agent 5-aza-2’-deoxycytidine (DAC) on metastatic melanoma

UV exposure-induced oxidative stress is implicated as the driving mechanism of melanoma development. Increased oxidative stress results in imbalanced reactive oxygen species (ROS) that damage DNA and dysregulated epigenetic modifications and leads to melanoma progression. Sulforaphane (SFN) is the natural bioactivated product of the cruciferous vegetable family (e.g., broccoli and Brussels sprouts) and is known to play a dual role in cytoprotection and to induce apoptosis in the tumor via antioxidant regulation and histone modification of epigenetic enzymes. We investigated the combinational effect of 5-aza-2’-deoxycytidine (DAC), an FDA-approved DNA-modification epigenetic drug and SFN in melanoma cells. We found further cell growth inhibition and an increased number of altered gene expression profiles, increased survival-related cytokine expression, as well as unique histones post-translational modifications (PTMs) upon combinational treatments compared to single treatment in vitro. These results set the stage for animal studies. The long-term goal of the current study is to find an optimal dietary dose of antioxidants from SFN to reduce the burden of oxidative stress, which may contribute to melanoma recurrence, a constant problem with current treatments. In addition to recurrence, a reduced dose of epigenetic drugs applied may minimize the side effects of single-high-dose treatment.

Citation Format: Tung-chin Chiang, L. Joseph Su, Brian S. Koss, Charity Washam, Stephanie Byrum, Aaron Storey, Alan J. Koss. Combinational effect of sulforaphane (SFN) and epigenetic demethylation agent 5-aza-2’-deoxycytidine (DAC) on metastatic melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr B26.

Electronic structure and trilayer growth of indium films on Si(111): a photoemission study

We report on the preferred trilayer growth of indium films on Si(111) studied by angle-resolved photoemission spectroscopy. By employing an interfactant and optimized annealing conditions, the kinetic constraint on the In atoms due to the substrate is greatly reduced and 'electronic growth'-where film morphology is controlled by the quantized electronic structure of the film-can be achieved at low coverage. Our photoemission spectra reveal that films of 4 ML (monolayers) and 7 ML thicknesses are energetically favored due to a lower surface energy, as confirmed by theoretical calculations. A detailed comparison of the photoemission spectra between In films grown on the In-√3 × √3/Si(111) surface and those on the Si(111) 7 × 7 surface shows that the √3 × √3 interfactant is a better template for growing In films at low coverage and effectively reduces the electronic coupling between the film and the substrate. In addition, the observed band structures of In films are in reasonable agreement with first-principles calculations and suggest that In films grown on the √3 × √3 interfactant might already be close to the bulk-like body-centered tetragonal structure at around 10 ML.

Thermal stability and electronic structure of atomically uniform Pb films on Si(111)

Atomically uniform Pb films are successfully prepared on Si(111), despite a large lattice mismatch. Angle-resolved photoemission measurements of the electronic structure show layer-resolved quantum well states which can be correlated with dramatic variations in thermal stability. The odd film thicknesses N = 5, 7, and 9 monolayers show sharp quantum well states. The even film thicknesses N = 6 and 8 do not, but are much more stable than the odd film thicknesses. This correlation is discussed in terms of a total energy calculation and Friedel-like oscillations in properties.

DNA hypomethylation and imbalanced expression of DNA methyltransferases (DNMT1, 3A, and 3B) in human uterine leiomyoma

OBJECTIVE

Despite the high prevalence of uterine leiomyoma in women, little is known about the pathophysiology of this tumor. This study intends to define the epigenetic modulation of this tumor.

METHODS

Twenty-three pairs of leiomyomas and their adjacent myometria were collected. Status of DNA global methylation was determined by using DNA methyl acceptance assay and immunohistochemistry staining with 5-methylcytidine antibody. MRNA level of DNA methyltransferases (DNMT1, 3A, and 3B) was assessed by quantitative real time PCR.

RESULTS

DNA global hypomethylation was detected in the leiomyoma tissues as compared with the adjacent myometria. DNMT1 expression was increased in 47.5% and was equal in 47.5% in leiomyomas compared to the adjacent myometria. On the other hand, over 74% of cases showed decreased expression of DNMT3A and 3B in leiomyomas compared to the adjacent myometria.

CONCLUSION

Global hypomethylation and imbalanced expression of DNMTs in uterine leiomyoma suggested a potential mechanism of epigenetic modulation in the development of this tumor.

Atomistics of Ge deposition on Si(100) by atomic layer epitaxy

Chlorine termination of mixed Ge/Si(100) surfaces substantially enhances the contrast between Ge and Si sites in scanning tunneling microscopy observations. This finding enables a detailed investigation of the spatial distribution of Ge atoms deposited on Si(100) by atomic layer epitaxy. The results are corroborated by photoemission measurements aided by an unusually large chemical shift between Cl adsorbed on Si and Ge. Adsorbate-substrate atomic exchange during growth is shown to be important. The resulting interface is thus graded, but characterized by a very short length scale of about one monolayer.

Quantum Electronic Stability of Atomically Uniform Films

We have studied the structural stability of thin silver films with thicknesses of N = 1 to 15 monolayers, deposited on an Fe(100) substrate. Photoemission spectroscopy results show that films of N = 1, 2, and 5 monolayer thicknesses are structurally stable for temperatures above 800 kelvin, whereas films of other thicknesses are unstable and bifurcate into a film with N +/- 1 monolayer thicknesses at temperatures around 400 kelvin. The results are in agreement with theoretical predictions that consider the electronic energy of the quantum well associated with a particular film thickness as a significant contribution to the film stability.

X-ray studies of phonon softening in tise2

The charge-density-wave transition in TiSe (2), which results in a commensurate (2x2x2) superlattice at temperatures below approximately 200 K, presumably involves softening of a zone-boundary phonon mode. For the first time, this phonon-softening behavior has been examined over a wide temperature range by synchrotron x-ray thermal diffuse scattering.

Gene imprinting in developmental toxicology: a possible interface between physiology and pathology

Gene imprinting is an epigenetic mechanism for accomplishing persistent change in gene expression. In this brief paper, we explore the mechanisms for imprinting genes and present data showing that the synthetic estrogen, diethylstilbestrol (DES) can developmentally imprint genes by changing the pattern of DNA methylation. We further discuss the implications of this and other findings for non-mutagenic aspects of developmental toxicology, and suggest ways to use this concept in modifying in vitro screening for developmental toxicants.

Decreased expression of Wnt7a mRNA is inversely associated with the expression of estrogen receptor-alpha in human uterine leiomyoma

Wnt-7a gene not only guides the development of the anterior-posterior axis in the female reproductive tract, but also plays a critical role in uterine smooth muscle pattering and maintenance of adult uterine function. This gene is also responsive to changes in the levels of sex steroid hormone in the female reproductive tract. To explore the molecular mechanisms underlying the pathogenesis of uterine leiomyoma, the expression of Wnt7a mRNA in the leiomyoma has been assessed. RT-PCR was performed on uterine leiomyomas and the adjacent myometria. Of 30 cases of leiomyomas studied, 67% showed a decreased mRNA level as compared to the paired myometria. On the other hand, estrogen receptor-alpha (ER-alpha) mRNA is hyper-expressed in 67% of the leiomyomas as compared to their paired myometrium. An inverse association at mRNA expression was found between Wnt7a and ER-alpha. Miller et alhas shown that fetal exposure of DES results in de-regulation of Wnt7a during uterine morphogenesis. Referring to their results, we have postulated that hypersensitivity of leiomyoma cells to estrogen may deregulate the Wnt7a expression. Decreased expression of Wnt7a may lead to loss of control in patterning of the myometrium and result in development of leiomyoma

Differences in protein kinase C and estrogen receptor alpha, beta expression and signaling correlate with apoptotic sensitivity of MCF-7 breast cancer cell variants

Widespread use of MCF-7 human breast cancer cells as a model system for breast cancer has lead to variations in these cells between different laboratories. Although several reports have addressed these differences in terms of proliferation and estrogenic response, differences in sensitivity to apoptosis have just begun to be described. Based on the possible differences in apoptotic sensitivity that may arise due to the existence of MCF-7 cell variants, we determined the relative sensitivity of MCF-7 cell variants from three established laboratories (designated M, L and N) to known inducers of apoptosis. Consistent with our previous studies we demonstrate that differences exist among these variants in regards to tumor necrosis factor alpha (TNF)-induced cell death and inhibition of proliferation in a dose-dependent manner. To establish if the difference in apoptotic susceptibility was specific to TNF, the three MCF-7 cell variants were tested for their response to other known inducers of apoptosis: okadaic acid, staurosporine and 4-hydroxy-tamoxifen. Viability and DNA fragmentation analysis revealed a similar pattern of resistance to apoptosis by all agents in the MCF-7 M variant. The MCF-7 L variant was resistant to okadaic acid and 4-hydroxy-tamoxifen but not staurosporine. In contrast, MCF-7 N cells were sensitive to induction of apoptosis by all agents. The role of both protein kinase C (PKC) and estrogen signaling in the regulation of cell survival prompted investigation of these pathways as a mechanism for differential sensitivity of MCF-7 cell variants to apoptosis. While both estrogen receptor alpha (ERalpha) and ERbeta were expressed in MCF-7 M and N cells, the absence of ERbeta in MCF-7 L cells correlated with decreased estrogen responsiveness of the L variant. Variations in estrogenic responsiveness and PKC isoform expression may account for the enhanced susceptibility of both the L and N variants to staurosporine.

Surgical treatment of bronchiectasis: 10 years' experience

BACKGROUND

Since antibiotic therapy and vaccination have been widely used in medical practice, the incidence of bronchiectasis has decreased steadily. The principal role of surgery associated with this disease is for the treatment of complications. We present an analysis of surgical results during a 10-year period.

METHODS

The medical records of bronchiectasis patients who were surgically treated were retrospectively reviewed from July, 1987, to March, 1998. The surgical indications, complications and recurrences of bronchiectasis were evaluated.

RESULTS

A total of 41 bronchiectasis patients underwent surgical treatment from 1987 to 1998 at our hospital. There were 18 males (mean age, 37.8 +/- 15.3 years; range, 16-73 years), and 23 females (mean age, 33 +/- 7.1 years; range, 21-46 years). The indications for surgery were hemoptysis in 30, failed medical treatment in eight, suspected neoplasm in two and retention of a foreign body in one patient. Anatomic resections of the diseased sites were carried out more frequently on the left lower lobes of the lungs. In total, there were 20 left lower lobes, five right lower lobes, 10 left lingular lobes, five right middle lobes, four left upper lobes and one right upper lobe that required surgery. Surgical complications included hemorrhage in one patient, bronchopleural fistula in one and galactorrhea in one patient. The follow-up intervals were from two to 131 months (mean, 72.5 +/- 37.6 months; median, 74 months). There were two cases of recurrent symptoms and six cases of recurrent hemoptysis; all were easily controlled by medication. There were no mortalities.

CONCLUSIONS

Surgical treatment of bronchiectasis yields immediate resolution of symptoms, better quality of life and no mortalities. Cessation of smoking, avoiding air pollution and careful medical follow-up are mandatory.

Dead-on-arrival patients in Panchiao, Taipei

BACKGROUND

The present emergency medical service (EMS) system in the Panchiao area includes operations in Panchiao, Sulin, Sunshia, Chung Ho and Touchen, which is in the early developmental stage. Educational programs such as emergency medical technician (EMT)-I, and -II have been provided for less than 25% of firefighters in that area. Several mass educational programs in cardiopulmonary resuscitation (CPR) were also provided for the inhabitants of the area. The purpose of this study was to establish a database of dead-on-arrival (DOA) patients during this early stage of the EMS system development so that comparisons of EMS performance could be assessed to identify any future needs of the EMS system in the Panchiao area.

METHODS

A patient was verified as DOA if there was no pulse nor a response to stimulation. For every DOA patient, several parameters were recorded in a registration book, which began January 1, 1995, and included the following: name, gender, age, mode of transportation, time to hospitalization, on-scene CPR, prehospital basic life support, possible etiology, response to advanced cardiac life support (ACLS), disposition and outcome. The registration book was reviewed and a follow-up study was designed, which covered the entire year of 1995.

RESULTS

There were 292 DOA patients brought to the emergency room of the Far Eastern Memorial Hospital in Panchiao, Taipei, between January 1, 1995, and December 31, 1995. The study population comprised 190 (65.1%) men and 102 (34.9%) women. The mean age of the men was 51.8 +/- 22.3 years (mean +/- standard deviation). The mean age of the women was 59.8 +/- 24.4 years. Emergency service ambulances transported most DOA patients, though a few were transported by private ambulance from nursing homes. There were only two incidents in which prehospital CPR was conducted. The time to hospitalization varied from five to 170 minutes and averaged 38.3 minutes. Following ACLS, 244 (83.6%) patients were pronounced dead in the emergency room. Cardiovascular and respiratory problems were the leading etiologies and trauma was the second. There were 48 patients (16.4%) who responded to ACLS, but only eight (2.7%) survived until hospital discharge.

CONCLUSIONS

Delayed initiation of the EMS system resulted in an average time to hospitalization of 38.3 minutes. Cardiovascular collapse was the leading etiology in DOA patients. There were only two patients who received prehospital CPR, suggesting that layperson CPR and EMT education cannot be overemphasized.

Buspirone impaired acquisition and retention in avoidance tasks: involvement of the hippocampus

This study investigated the effects of buspirone on acquisition as well as formation and expression of memory in three different types of avoidance tasks. Rats were trained and tested on a one-trial inhibitory avoidance task, an 8-trial active avoidance task or the Morris water maze. Buspirone (5.0 mg/kg) was administered subcutaneously 30 min before training, immediately after training or 30 min before testing. Retention was tested at various times after training. In the inhibitory avoidance task, pretraining injections of buspirone produced a marked impairing effect on retention, posttraining injections of buspirone produced a moderate but time-dependent memory deficit. Pretest injections of buspirone suppressed retention performance. Such an effect was more pronounced in the 1-day test than in the 21-day test. Intra-hippocampal infusion of buspirone (5.0 micrograms) before testing suppressed expression of the 1-day, but not the 21-day, memory. In the active avoidance task and the Morris water maze, an injection of buspirone before training or testing also impaired acquisition or suppressed retention performance. These findings suggest that buspirone given at various times could compromise acquisition, consolidation and retrieval of affective memory and the hippocampus was involved in the retrieval effect.

Digitizing of radiographs with a roller-type CCD scanner

OBJECTIVES

Roller-type scanners can be used to digitize radiographs. This study evaluated the physical performance of a roller-type scanner with regard to dynamic range, scan reproducibility, and homogeneity.

METHODS

A VXR-12 (Vidar System Corp., Herndon, Va.) roller-type scanner with imaging editing software Paint Shop Pro (JASC Inc., Minnetonka, Minn.) was used to digitize a step tablet image on Kodak T-MAT G films (Kodak, Rochester, N.Y.). The step tablet image was scanned at various locations and with different scanning settings. The pixel values of the resulting image were analyzed. The step tablet image was also scanned by a Wellhofer WD 102 Filmdensitometer (Wellhofer Dosimetrie, Schwarzenbruck, Germany) to measure the optical densities of the steps on the film for comparison.

RESULTS

With the use of the default scanning settings the digitized images had pixel values distributed in a similar dynamic range to that of the film densitometer. This scanner produced consistent images with different scanning positions, different orientation of the images, and different power states of the scanner.

CONCLUSIONS

This roller-type scanner has a similar dynamic range to that of the film densitometer. The operating condition of the scanner is stable, and the resulting image is not significantly affected by the scanning positions. This type of scanner should be suitable for digitizing dental x-ray films, although the limiting scanning resolution might not be sufficient for some diagnostic purposes.

[Giant cystic hygroma: a case report]

Cystic hygromas are congenital malformations of the lymphatic system appearing as single or multiloculated, fluid-filled cavities found mainly in the neck and axilla region. Antenatal ultrasound examination done in this case showed a suspicious giant cystic mass over the neck and chest area. At birth, the mass turned out to be a rare giant cystic hygroma measuring about 25cm x 26cm covering neck, anterior chest, axilla, proximal right upper limb, upper abdomen and upper back area. Because of some compromise to the infant's breathing, an emergency resection was done, and the infant tolerated the procedure well. Pathology report confirmed the diagnosis.

Boerhaave's syndrome--successful treatment of a late case

A case of spontaneous rupture of the esophagus (Boerhaave's Syndrome) underwent medical treatment as acute myocardial infarction as initial impression, delay diagnosed 16 days after acute event, and subsequently treated successfully, is presented. Because the patient was critically ill, a conservative management was approached, i.e., NG tube decompression, tube thoracostomy, gastrostomy, broad spectrum antibiotics, TPN to jejunostomy enteral feeding. The patient was salvaged successfully and recovered without complication. The initial unawareness of mediastinal emphysema on chest film resulted in delayed diagnosis.

Rapid, low-cost cleanup procedure for determination of semivolatile organic compounds in human and bovine adipose tissues

A gas chromatographic/mass spectrometric (GC/MS) method is described for determination of organic environmental pollutants in human and bovine adipose tissues. Compounds such as organochlorine pesticides, polychlorinated biphenyls, polynuclear aromatic hydrocarbons, polychlorinated aromatics, and brominated aromatics are extracted with organic solvents and separated from coextracted lipids on a Florisil column. The eluate is concentrated and compounds are identified and quantitated by GC/MS analysis. The method was evaluated in a single laboratory for ability to recover compounds of environmental and regulatory importance. Except for a few more polar compounds, such as phthalates and phosphates, recoveries averaged about 85%. The elution system maximized recovery and allowed minimal coelution of lipid materials. Detection limits for most compounds studied were in the range of 5-50 ng/g (ppb).

Synthesis and in vitro bioactivity of human growth hormone-releasing factor analogs substituted with a single D-amino acid

Fifty-four analogs of human growth hormone-releasing factor (hGRF) substituted with a single D-amino acid were synthesized by solid phase methodology. Their capacity to release growth hormone was tested on rat anterior pituitary cells in monolayer culture. Among the series of 28 analogs, which had the amino acid at each position of hGRF (1-29)NH2, except glycine at position 15, substituted by the corresponding D-isomer, [D-Ala2]-, [D-Asp3]-, [D-Asn8]-, [D-Tyr10]-, [D-Asp25]-, [D-Met27]-, [D-Ser28]-, and [D-Arg29]hGRF(1-29)NH2 were as potent as hGRF(1-29)NH2, while [D-Ile5]-, [D-Phe6]-, [D-Thr7]-, and [D-Val13]hGRF(1-29)NH2 showed quite low potencies. Effects of substitution with other D-amino acids in positions 2,3,8,9,10 and 11 were also studied. In most cases, the resulting analogs showed decreased potency, but still retained high intrinsic activity. Only [D-Arg2]hGRF(1-29)NH2 showed very low intrinsic activity and some antagonistic property.

Use of solid phase Florisil cartridges to separate fat from semivolatile organic compounds in adipose tissue

A quick method for separation of semivolatile organic compounds from fat in adipose tissue has been developed. This method uses commercially available solid phase cartridges for sample cleanup. The results indicate that the recoveries, from hexane-extracted fat, of 4 representative classes of organic compounds range from 86.2 to 116%. The solid phase cartridges provide excellent separations of the fat from the analytes; no extraneous interference peaks were detected in the gas chromatograms. The method requires only 0.1 g sample and is quick and simple to use. Although results are reported for samples containing 1-14 ppm, the final extract can be concentrated to a volume allowing detection between 10 and 100 ppb.

Synthesis and in vitro bioactivity of human growth hormone-releasing factor analogs substituted at position-1

Eight position-1 analogs of the 40-amino acid fragment and two position-1 analogs of human growth hormone-releasing factor were synthesized by solid phase methodology and their capacity to release growth hormone was determined using rat anterior pituitary cells in monolayer culture. Relative to hGRF(1-40)OH, which was arbitrarily assigned a potency value of 1, [D-Tyr1]hGRF(1-40)OH, [Phe1]hGRF(1-40)OH, [Trp1]hGRF(1-40)OH, [His1]hGRF(1-40)OH, [Ala1]hGRF(1-40)OH, [(-Ac)Tyr1]hGRF(1-40)OH, Arg0-hGRF(1-40)OH and Ala0-hGRF(1-40)OH have potencies of 0.022, 0.038, 0.003, 0.351, 0.010, 0.032, 0.002 and 0.007 respectively. Relative to hGRF(1-44)NH2 = 1, [(3-Me)His1]hGRF(1-44)NH2 and [(O-Me)Tyr1]hGRF(1-44)NH2 have potencies of 0.132 and 0.001 respectively. These results demonstrate the prerequisite for an aromatic residue at position-1 for potent biological activity and also suggest that the capacity for hydrogen bond formation with the first residue is required for full receptor-ligand interaction.

New Oleanene-type Triterpenes from Abrus precatorius and X-ray Crystal Structure of Abrusgenic Acid-Methanol 1:1 Solvate

From ABRUS PRECATORIUS Abl. triterpenoids abruslactone, methyl abrusgenate and abrusgenic acid were isolated and elucidated by spectroscopic and X-ray techniques.

Isolation and structural elucidation of some sapogenols from Abrus cantoniensis

After hydrolysis of the saponin fraction of the roots of Abrus cantoniensis, a new triterpenoid sapogenol, cantoniensistriol, was isolated together with sophoradiol, soyasapogenol B and soyasapogenol A. The structures of cantoniensistriol and sophoradiol were elucidated by spectroscopic methods. On the basis of the relation between cantoniensistriol and soyasapogenol A, the steric assignment of the C-21 and C-22 hydroxyl groups of the latter was discussed.

Gas chromatographic-mass spectrometric assay for low levels of retinoic acid in human blood

A rapid and sensitive method of analysis for retinoic acid in human blood has been developed using gas chromatography-mass spectrometry for separation and detection. The retinoic acid is isolated by solvent extraction into petroleum ether, and converted to methyl retinoate by reacting with dimethylformamide dimethylacetal. The method has been applied to the study of retinoic acid in human blood after subtotal inunction, total inunction and intravenous injection of retinoic acid. The sensitivity limit of 1 ng/ml blood is realized with a 10-ml blood sample.

The nasopharyngoscope and camera examination of the primary carcinoma of nasopharynx

The site of origin, the histology, the morphology, the extent, and the T category of the primary carcinoma of nasopharynx and their correlations, including incidence of cervical lymph node metastasis, of 159 consecutive cases seen in a period of four years are studied.

Visible, optical rotatory dispersion, and paramagnetic resonance spectra of the L-histidine--cu(II)--L-threonine complex

The stability constant of L-histidine-Cu(II)-L-threonine relative to Cu(II)-L-histidine and Cu(II)-L-threonine has been determined. The absorption maxima of Cu(II)-L-histidine and Cu(II)-L-threonine were shown to be at 645 mμ and 625 mμ respectively and a solution containing a mixture of L-histidine, Cu(II), and L-threonine in a 1:1:1 molar ratio shows an absorption maximum at 615 mμ. Shifts in absorption spectra and changes in the optical density were observed when the relative concentration of the ligands in the mixture was changed. The optical rotatory dispersion studies reveal that, in the region 640–700 mμ, it is especially apparent that the molar rotation of the mixed solution is by no means an average of the molar rotation of the Cu(II)-L-histidine and Cu(II)-L-threonine complexes. The three complexes show a close overall similarity of the electron paramagnetic resonance (EPR) parameters. The EPR spectrum of cupric complexes in the mixed solution resembles both the L-threonine and L-histidine complexes in its main features but it differs in significant detail from each of them. The hyperfine splitting of the mixed complex in solution is evidently greater than that of either the Cu(II)–L-histidine or Cu(II)–L-threonine. A structure for L-histidine–Cu(II)–L-threonine is proposed.