Chondro/osteoblastic and cardiovascular gene modulation in human artery smooth muscle cells that calcify in the presence of phosphate and calcitriol or paricalcitol

Vitamin D sterol administration, a traditional treatment for secondary hyperparathyroidism, may increase serum calcium and phosphorus, and has been associated with increased vascular calcification (VC). In vitro studies suggest that in the presence of uremic concentrations of phosphorus, vitamin D sterols regulate gene expression associated with trans-differentiation of smooth muscle cells (SMCs) to a chondro/osteoblastic cell type. This study examined effects of vitamin D sterols on gene expression profiles associated with phosphate-enhanced human coronary artery SMC (CASMC) calcification. Cultured CASMCs were exposed to phosphate-containing differentiation medium (DM) with and without calcitriol, paricalcitol, or the calcimimetic R-568 (10(-11)-10(-7) M) for 7 days. Calcification of CASMCs, determined using colorimetry following acid extraction, was dose dependently increased (1.6- to 1.9-fold) by vitamin D sterols + DM. In contrast, R-568 did not increase calcification. Microarray analysis demonstrated that, compared with DM, calcitriol (10(-8) M) + DM or paricalcitol (10(-8) M) + DM similarly and significantly (P < 0.05) regulated genes of various pathways including: metabolism, CYP24A1; mineralization, ENPP1; apoptosis, GIP3; osteo/chondrogenesis, OPG, TGFB2, Dkk1, BMP4, BMP6; cardiovascular, HGF, DSP1, TNC; cell cycle, MAPK13; and ion channels, SLC22A3 KCNK3. R-568 had no effect on CASMC gene expression. Thus, SMC calcification observed in response to vitamin D sterol + DM may be partially mediated through targeting mineralization, apoptotic, osteo/chondrocytic, and cardiovascular pathway genes, although some gene changes may protect against calcification. Further studies to determine precise roles of these genes in development of, or protection against VC and cardiovascular disease are required.

Rectal cancer: 3D dynamic contrast-enhanced MRI; correlation with microvascular density and clinicopathological features

PURPOSE

The primary aim of this prospective study was to evaluate the relationship between three-dimensional dynamic contrast-enhanced magnetic resonance (3D-DCE-MR) imaging parameters and clinicopathological features of rectal cancer and assess their potential as new radiological prognostic predictors.

MATERIALS AND METHODS

Three-dimensional DCE-MR was performed on 26 cases of pathologically proved rectal adenocarcinoma 1 week prior to operation. Data were analysed to calculate transfer constant (Ktrans), leakage space (Ve) and rate constant (Kep) of both tumour and normal rectal wall. Microvessel density (MVD) was evaluated by immunohistochemical staining of surgical specimens. All findings were analysed prospectively and correlated with tumour/node/metastasis (TNM) staging, Dukes staging, histological grading, presence of lymph node metastasis, serosal involvement and MVD.

RESULTS

Mean Ktrans, Ve and Kep for tumours were as follows: Ktrans 7.123±3.850/min, Ve 14.2±3.0%, Kep 49.446±20.404/min, revealing the significant difference between the tumour and normal rectal wall (p=0.001). There was a significant difference for Ktrans not only between patients with and without lymphatic involvement (p=0.000), but also among Dukes staging (p=0.04) and pTNM staging (p=0.03). Kep showed moderate correlation with TNM stages (r=0.479, p=0.02). Ve and MVD revealed no significant correlation with the clinicopathological findings described above (p>0.05).

CONCLUSION

Owing to the moderate and strong relationship between Ktrans and clinicopathological elements, Ktrans might be the prognostic indicator of rectal cancer. Threedimensional DCE high-resolution MR imaging provides a competing opportunity to assess contrast kinetics.

Abstract P4-01-07: Endoplasmic Reticulum-Associated Calcium Regulates Resistance of the Anti-Apoptotic Protein Bcl-2 to Taxol-Induced Apoptosis in Breast Cancer Cells

Background: The unique anti-apoptotic function of Bcl-2 results in cellular resistance to many chemotherapeutic agents used in solid tumor treatments. However, there is a controversy regarding the relationship between Bcl-2 resistance and the mechanism of action for Taxol, an anticancer agent commonly used in breast cancer treatment. Although previous studies showed both Bcl-2 and Taxol may have effects on calcium homeostasis independently, no studies have addressed whether calcium is the keystone in the relationship between Bcl-2 resistance and Taxol action. Objective: Since most internal calcium is stored in the endoplasmic reticulum (ER), this study focused on the role of ER calcium changes in Bcl-2-activated resistance to Taxol-induced apoptosis. The ER calcium channel IP3R and its relationship with Bcl-2 and Taxol were investigated in order to clarify the mechanism underlying calcium regulation.

Methods and Materials: For this study, MDA-MB-468, a Bcl-2 negative breast carcinoma cell line, its Bcl-2 stable transfectant and MCF-7, a Bcl-2 positive breast carcinoma cell line were used. The dynamic calcium changes induced by Taxol in these cells were determined by measuring free cytosolic calcium fluctuations using Fluo4-AM and ER calcium changes by the calcium cameleon, D1ER. Taxol-induced apoptosis was measured using the Annexin V-FITC assay. The calcium interfering agents BAPTA-AM and 2-APB were applied to evaluate whether Taxol-induced calcium changes were related to this apoptotic event. Western blot was used to detect changes induced by Taxol treatment in Bcl-2 and IP3R protein levels.

Results: Taxol induced a rapid ER calcium release followed by a gradual ER calcium depletion in both Bcl-2 positive and negative cell lines, indicating that ER calcium store provides a direct target for Taxol, independently of Bcl-2 expression. Interfering with these calcium changes inhibited the Taxol-induced apoptosis, suggesting ER calcium release promotes Taxol-induced apoptosis. Our results also showed that Bcl-2 inhibited the basal ER calcium release. Taxol stimulated ER calcium release and thus attenuated Bcl-2-initiated resistance to apoptosis. Relevance: This research addressed the question of whether ER calcium changes play a critical or marginal role in mediating resistance of Bcl-2 to Taxol-induced apoptosis. Elucidating the role of calcium in this process will not only help to clarify the mechanism of drug resistance associated with Bcl-2, but also aid in more effective application of Taxol in breast cancer treatment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-01-07.

Characterization of immune responses following intranasal immunization with the Mycobacterium bovis CFP-10 protein expressed by attenuated Salmonella typhimurium

Culture filtrate protein 10 (CFP-10) from Mycobacterium bovis or Mycobacterium tuberculosis (MTB) is an immunodominant T-cell antigen expressed during the early stages of infection. Because lungs are most commonly associated with primary M. bovis infections, specific immunity at this site is desirable for protection. Therefore, in this study, immune responses generated in mouse lung, spleen and Peyer's patches were examined following intranasal (i.n.) immunization with Salmonella typhimurium- expressing CFP-10. Cells harvested from the lungs and Peyer's patches of immunized mice and then stimulated with CFP-10 produced significant levels of IFN-γ and these mice developed elevated serum IgG and lung IgA anti-CFP-10 responses, suggesting that this approach induced potent anti-CFP-10 mucosal immunity. Our study demonstrates that i.n. administration of CFP-10 expressed by S. typhimurium represents an effective way to induce efficient immune response to M. bovis antigen.

Epidermal growth factor receptor transactivation by the cannabinoid receptor (CB1) and transient receptor potential vanilloid 1 (TRPV1) induces differential responses in corneal epithelial cells

Corneal epithelial injury induces release of endogenous metabolites that are cannabinoid receptor 1 (CB1) and transient receptor potential vanilloid 1 (TRPV1) agonists. We determined the functional contributions by CB1 and TRPV1 activation to eliciting responses underlying wound healing in human corneal epithelial cells (HCEC). Both the selective CB1 and TRPV1 agonists (i.e., WIN55,212-2 [WIN] and capsaicin [CAP], respectively) induced EGFR phosphorylation whereas either inhibition of its tyrosine kinase activity with AG1478 or functional blockage eliminated this response. Furthermore, EGFR transactivation was abolished by inhibitors of proteolytic release of heparin bound EGF (HB-EGF). CB1-induced Ca(2+) transients were reduced during exposure to either the CB1 antagonist, AM251 or AG1478. Both CAP and WIN induced transient increases in Erk1/2, p38, JNK1/2 MAPK and Akt/PI-3K phosphorylation status resulting in cell proliferation and migration increases which mirrored those elicited by EGF. Neither EGF nor WIN induced any increases in IL-6 and IL-8 release. On the other hand, CAP-induced 3- and 6-fold increases, which were fully attenuated during exposure to CPZ, but AG1478 only suppressed them by 21%. The mixed CB1 and TRPV1 antagonist, AM251, enhanced the CAP-induced rise in IL-8 release to a higher level than that elicited by CAP alone. In conclusion, CB1 and TRPV1 activation induces increases in HCEC proliferation and migration through EGFR transactivation leading to global MAPK and Akt/PI-3K pathway stimulation. On the other hand, the TRPV1-mediated increases in IL-6 and IL-8 release are elicited through both EGFR dependent and EGFR-independent signaling pathways.

The roles of microRNAs in heart diseases: a novel important regulator

MicroRNAs (miRNAs) are non-coding single-stranded RNAs with about 21~23 nucleotides in length, which originate from encoding genes in nucleus. miRNAs play an inhibitory role in gene expression in a post-transcriptional level by partially complementary binding to the 3' unstranlated region (UTR) of target mRNAs. Large bodies of evidence have shown that miRNAs were involved in various diseases, such as cancer, infectious diseases, diabetes etc, and rising as critical modulators of pathological processes. Lately, some highlight articles revealed that the altered expression of miRNAs such as miR-1, miR-133, miR-21, miR-208 etc in hearts also contributed to cardiovascular diseases, such as heart ischemia, cardiac hypertrophy, and arrhythmias. Moreover, miRNAs were also identified to regulate heart development. These exciting findings not only improve our understanding of the molecular mechanisms of heart diseases, but also provide a new class of potential molecular targets. miRNAs, for the development of novel agents to treat heart diseases. Here, we summarized the recent discoveries about the role of miRNAs in cardiac physiological and pathological functions, and then discussed about their therapeutic potentials for heart diseases.

Increased short circuit current in organic photovoltaic using high-surface area electrode based on ZnO nanowires decorated with CdTe quantum dots

A photosensitized high-surface area transparent electrode has been employed to increase the short circuit current of a photovoltaic device with a blend of poly(3-hexylthiophene) (P3HT) and (6,6)-phenyl C61 butyric acid methyl ester (PCBM) as the active layer. This is achieved by directly growing ZnO nanowires on indium tin oxide (ITO) film via a physical vapor method. The nanowire surface is then decorated with CdTe quantum dots by pulsed electron-beam deposition (PED). The nanowires alone provided a 20-fold increase in the short circuit current under visible light illumination. This was further increased by a factor of approximately 1.5 by the photosensitization effect of CdTe, which has an optical absorption of up to 820 nm.

Coculturing embryonic stem cells with damaged hepatocytes leads to restoration of damage and high frequency of fusion

Controversy surrounds issue of cell fusion as a repair mechanism whereby stem cells regenerate. To identify the ratio of fusion happens between stem cells and damaged cells, hepatic cells were damaged with 200microM H2O2 for 2 hr. Then, mouse ESCs were cocultured with damaged human hepatocytes. Fusion was detected directly by karyotyping after 48hr coculture as well as by Oct4 promoter drove GFP signal. Results showed that average ratio of fusion in undamaged control group was 0.031 per thousand while ratio of fusion in damaged group was 0.357 per thousand, which was 10 times higher than fusion happened in the control group. Meanwhile, GFP signal indicated that fusion induced hepatic cells' Oct-4 reactivation. Fusion derived hybrid cells contained chromosomes from both parental cells. Most of the chromosomes were from damaged human hepatic cells. Activity of damage-related enzymes LDH, SGOT and SGPT were significantly lower at 48hr coculture than at 12hr coculture. Expression of albumin in co-culture system was up-regulated after coculture, which indicated the reparation of damage after coculturing. Also, by applying RT-PCR and immunocytochemistry differentiation status of ES cells were evaluated. It was shown that ES cells differentiated to hepatic lineage cells and expressed hepatic genes and proteins.

Temporal trends in cause-specific late mortality among five-year survivors of childhood cancer

10004

Background: Five-year survival rates for childhood cancer have increased over the past 4 decades, increasing the number of long-term survivors. Among 5-yr survivors, the impact of changes in therapy on cause-specific late mortality has not been thoroughly assessed. Methods: Late mortality was evaluated over 3 eras (1974–81, 1982–90, 1991–2000) in 26,643 5-year survivors diagnosed <21 years of age from the SEER population-based registry. Cause-specific mortality was categorized as death from recurrence/progression of primary disease, external causes, and non-recurrence/non-external causes (Non-Recur/Ext) (i.e., deaths from health conditions including sequelae of cancer therapy). Results: All-cause and Recurrence mortality was significantly lower in more recent eras ( Table ). No significant improvement in late mortality attributable to Non-Recur/Ext causes was seen. Additionally, all-cause mortality was significantly lower in more recent eras for 5-year survivors of ALL, AML, Hodgkin, NHL, and CNS tumors, but not neuroblastoma and Ewing's Sarcoma where an increase in cumulative incidence of late mortality was seen in more recent eras. Significant improvement in late mortality from Recurrence by era was seen in most diagnostic groups. Conclusions: All-cause late mortality has improved with more recent eras, attributable to reduced rates of mortality from progression of primary disease (i.e., durable remission). Importantly, however, efforts to reduce the toxicity of more recent therapies have not produced detectable reduction in mortality attributable to other health conditions including sequelae of cancer therapy (non-Recur/Ext causes of death), which would include death from second malignancy, cardiac and pulmonary conditions. Worsening late mortality for 5-year survivors of neuroblastoma and Ewing's sarcoma may be due to improved use of salvage therapies that delay, but do not ultimately prevent death. [Table: see text]

No significant financial relationships to disclose.

Effect of berry size and sodium hydroxide pretreatment on the drying characteristics of blueberries under infrared radiation heating

This research studied the effect of berry size and dipping pretreatment in hot sodium hydroxide (NaOH) solution on the drying characteristics of blueberries under infrared radiation (IR) heating. Changes in the microstructure and diffusion coefficient of the berries after the NaOH pretreatment were also determined using scanning electronic microscopy and dynamic vapor sorption (DVS), respectively. To quantify the effect of berry size, non-pretreated bulk blueberries were sorted into 6 groups based on their diameters and dried at 70 degrees C. To determine the effectiveness of NaOH pretreatment in improving drying characteristics, bulk blueberries of different sizes, both nonpretreated and NaOH pretreated, were dried at constant temperatures of 80 and 90 degrees C, and variable temperatures of 70 degrees C for 50 min followed by 90 degrees C for 50 min. The NaOH pretreatment dipped blueberries in 0.1% NaOH solution with fruit to solution ratio 1:1 (w/v) at initial temperature of 93 degrees C for 5 s. Results showed that the drying rate increased with decreased berry size. Average moisture diffusivity was in the range of 5.89 to 8.13 m2/s at 70 degrees C. The NaOH pretreatment increased drying rate and moisture diffusivity and reduced the number of broken berries, especially at high drying temperatures. Results from SEM observation and DVS showed that the increase in diffusivity coefficients of berry coat and loss of intact microstructure in coat and tissue cells might contribute to the effect of NaOH pretreatment on the IR drying of blueberries.

Effects on human eyes caused by experimental exposures to office dust with and without addition of aldehydes or glucan

Thirty-six volunteers (in three susceptibility groups: 11 subjects were non-allergic with nasal histamine hypersensitivity, 13 were non-allergic with normal sensitivity, and 12 were pollen allergic with or without nasal hypersensitivity) were exposed for three and a half hours in a climate chamber. Each subject was exposed to clean air (dust 45 +/- 38 microg/m(3) total suspended particle, TSP), house dust at 357 +/- 180 microg/m(3) TSP, house dust 382 +/- 175 microg/m(3) TSP with added glucan (50 ng/m(3)) and house dust 394 +/- 168 microg/m(3) TSP with added aldehydes corresponding to a gaseous phase of 300 microg/m(3) in the air. The study was explorative by nature. No significant effects of exposures as such were seen on break-up time, conjunctival epithelial damage score and Trolox Equivalent Antioxidant Capacity (TEAC) in tear film and subjective ratings. However, in TEAC a significant different time course was seen during exposures to aldehyde-containing dust indicating a subacute and late response to the exposures. Perceived eye irritation increased significantly during exposures to normal dust. The perception ratings were highly correlated, whereas no correlation was found between the subjective responses and the objective measurements.

PRACTICAL IMPLICATIONS

The findings indicate that measurement effects on the eyes are rather insensitive measures of short time effects of office dust exposures.

Endoplasmic reticulum-associated calcium regulates taxol-induced apoptosis in breast cancer cells

Abstract #4163

Background: The body eliminates unhealthy cells through programmed cell-suicide called apoptosis. Calcium (Ca2+), one of the key regulators of cell survival, is also important in regulating apoptosis. Although the chemotherapeutic agent Taxol employs apoptosis to induce cell death in breast cancer treatment, the exact mechanism of how it induces apoptosis and the role of Ca2+ in this process remain unclear. The endoplasmic reticulum (ER), the main intracellular Ca2+ store, is newly-recognized as an important gateway in apoptosis, and possibly provides a target for Taxol.&#x2028; Objective/Hypothesis: Putting these facts together, our hypothesis is that ER Ca2+ changes induced by Taxol determine breast cancer cell susceptibility to apoptosis and thus play a key role in ER-associated apoptosis. Therefore, this study investigated whether Ca2+ changes, especially associated with the ER, were generated and related to this apoptotic event.&#x2028; Study Design and Methods: For this study, we used the MDA-MB-468 breast cancer cell line. The dynamic Ca2+ changes induced by Taxol were determined in living breast cancer cells by two methods: free cytosolic Ca2+ changes were measured using Fluo4-AM Ca2+ dye; and ER Ca2+ changes were measured by a novel Ca2+ cameleon, D1ER. After inducing and evaluating Taxol-induced apoptosis in this breast cancer cell line, the effects of different Ca2+ interfering agents on the apoptotic event were tested to determine whether Taxol-induced apoptosis is Ca2+ dependent.&#x2028; Results: Taxol has a direct effect on Ca2+ homeostasis. Taxol induces a rapid ER Ca2+ release and results in a transient increase in cytosolic Ca2+ levels. A gradual ER Ca2+ depletion developed and contributed to the final sustained cytosolic Ca2+ increase. Interfering with these Ca2+ changes inhibited the Taxol-induced apoptosis, indicating that ER Ca2+ promotes Taxol-induced apoptosis.&#x2028; Relevance: It is critical to understand the process through which the widely used anticancer agent Taxol induces apoptosis. This research addressed the question of whether intracellular Ca2+ changes play a critical or marginal role in mediating Taxol-induced apoptosis. Elucidating the role of calcium in this process will not only help to clarify the mechanism of Taxol, but also aid in more effective application of Taxol in breast cancer treatment.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4163.

Radiotherapeutic management of isolated local-regional recurrence following mastectomy

Abstract #5135

Background: Postmastectomy isolated local-regional recurrence(ILRR) remains a therapeutic challenge. This retrospective study aims to evaluate the role of radiotherapy(RT) in these patients and to analyze factors that influence local-regional control and survival.&#x2028; Methods: 255 pts with chest-wall(CW) and/or regional nodes recurrence(supraclavicular SC, axillary AXI and internal mammary nodes IMN) as first failure and received RT during 1990 and 2005 were analyzed, included 109 CW recurrence only, 114 regional nodes only and 32 pts with both, resulted in 304 recurrent sites. The median dose was 60Gy(47-74). Systemic treatment was give to 190 pts, including chemotherapy in 171, endocrine therapy(ET) in 69, and both in 41 pts.&#x2028; Results: The median disease-free interval(DFI) was 22 mo(2-260 mo), which were 37 and 17 mo in pts with positive hormonal receptor (HR) and negative HR respectively. Median follow-up was 45 mo (9 mo -15.5 yrs). The 2, 5 and 8-yr overall survival rate was 86.4%, 56.5% and 35% respectively. Median survival time after recurrence was 79 mo. The 2, 5 and 8-yr local control rate was 56.1%, 36.3% and 27.6% respectively. 79 second recurrence in the initial recurrent region and 83 subsequent recurrence in other local-regional sites were found.&#x2028; &#x2028; CW is the most common site of second recurrence. Multivariate analysis showed that no CW involvement, non-diffuse recurrence and radiation to the entire recurrent region were independent prognostic factors on local control of initial recurrent sites. ET proved to be the only independent prognostic factors on subsequent recurrence in other sites. In pts with CW recurrence, small field(67 pts) resulted in significantly lower 5-yrs local control compared to entire CW irradiation(74 pts) (33.6% vs 55.6%, p=0.023). Cox regression model found that DFI≥1yr, positive HR, solitary CW or non-supraclavicular nodal recurrence were independent favorable prognostic factors on overall survival .&#x2028; Conclusions: RT is an effective approach for ILRR after mastectomy. Radiation fields should cover the entire recurrent region. Elective irradiation to the CW in pts with nodal recurrence is recommended. Prognostic Index based on the positive multivariate analysis could be established as to stratify different prognostic sub-groups.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5135.

Association between nucleotide excision repair gene polymorphisms and chromosomal damage in coke-oven workers

The associations between several genetic polymorphisms of nucleotide excision repair genes (NER) and chromosome damage level were studied among 140 coke-oven workers exposed to a high level of polyaromatic hydrocarbons (PAHs) and 66 non-exposed workers. Seven polymorphisms with functional potential in five NER genes (ERCC1, ERCC2, ERCC4, ERCC5 and ERCC6) were genotyped in the 206 study subjects. Multivariate analysis of covariance revealed that coke-oven workers with the ERCC1 19007 CC genotype had significantly higher cytokinesis-block micronucleus frequency (CBMN) (10.5 +/- 6.8 per thousand) than those with CT (8.1 +/- 6.6 per thousand, p = 0.01) or TT (6.6 +/- 3.7-/ per thousand p = 0.05) or CT+TT genotypes (7.5 +/- 6.3 per thousand, p = 0.004). The ERCC6 A3368G polymorphism was also associated with CBMN frequency among coke-oven workers. Subjects with the AA genotype have a significantly higher CBMN frequency (10.0 +/- 6.9 per thousand) than those with AG (6.7 +/- 4.2 per thousand, p = 0.05) or AG+GG genotypes (6.6 +/- 4.1 per thousand, p = 0.02). Stratification analysis revealed the significant associations between ERCC1 C19007T and ERCC6 A3368G, and the CBMN frequencies were only found among older workers. In addition, a significant association between ERCC2 G23591A polymorphism and CBMN frequencies was also found among older coke-oven workers. The results suggest that polymorphisms of ERCC1 C19007T, ERCC6 A3368G and ERCC2 G23591A are associated with the CBMN frequencies among coke-oven workers.

[Study of the polyvinyl alcohol-collagen blend as wound dressing]

This study sought to explore a new compound polyvinyl alcohol-collagen as a wound dressing. To make the polymer, Polyvinyl alcohol (PVA) and collagen type I were put together in the ratio of 3:1, at the same time, polyethlene glycol as porogen was added, and the material was dried by air to be a membrane in shape. Then the ultimate tensile load, the hole diameter, porosity, and water absorption were measured. The cell biocompatibility was tested as well. The results showed the PVA-collagen blend had the average hole 100-150 microm in diameter, and the porosity about 90%. The ultimate tensile load reached 8.10 +/- 0.28 MPa, and water absorption was up to 185.42% +/- 6.93%. 3T3 cells grew well on the PVA-collagen member. Therefore, the PVA-collagen memberane is characterized not only by its ideal biomechanical ability and biocompability, but also by its ideal hole diameter, porosity and water absorption. It may have the potential for use as a wound dressing in vivo.