miR-448 negatively regulates ovarian cancer cell growth and metastasis by targeting CXCL12

OBJECTIVES

The purpose of the study is to investigate the roles of miR-448 in ovarian cancer.

METHODS

miR-448 and CXCL12 mRNA expression were examined using qRT-PCR. CXCL12 promoter activity was detected by luciferase activity system. Cell proliferation was assayed by MTT or colony formation. Migration and invasion was assayed by transwell chamber.

RESULTS

miR-448 expression was usually under-expressed in ovarian cancer tissues and cell lines compared with their normal ones. Ectopic expression of miR-448 inhibited cell proliferation, migration and invasion in ovarian cancer cells. Moreover, bioinformatic prediction suggested that CXCL12 was a target gene of miR-448. We also demonstrated that restored expression of CXCL12 dampened miR-448-mediated suppression of tumor progression, which suggests the important role of miR-448 in tumor progression.

CONCLUSION

Our data indicate that miR-448 functions as a tumor suppressor in ovarian cancer, which exerts its activity by suppressing the expression of CXCL12.

Concurrent IMRT and weekly cisplatin followed by GDP chemotherapy in newly diagnosed, stage IE to IIE, nasal, extranodal NK/T-Cell lymphoma

On the basis of the benefits of frontline radiation in early-stage, extranodal natural killer (NK)/T-cell lymphoma (ENKTL), we conducted the trial of concurrent chemoradiotherapy (CCRT) followed by three cycles of gemcitabine, dexamethasone and cisplatin (GDP). Thirty-two patients with newly diagnosed, stage IE to IIE, nasal ENKTL received CCRT (that is, all patients received intensity-modulated radiotherapy 56 Gy and cisplatin 30 mg/m² weekly, 3–5 weeks). Three cycles of GDP (gemcitabine 1000 mg/m² intravenously (i.v.) on days 1 and 8, dexamethasone 40 mg orally on days 1–4 and cisplatin 75 mg/m² i.v. on day 1 (GDP), every 21 days as an outpatient were scheduled after CCRT. All patients completed CCRT, which resulted in 100% response that included 24 complete responses (CRs) and eight partial responses. The CR rate after CCRT was 75.0% (that is, 24 of 32 responses). Twenty-eight of the 32 patients completed the planned three cycles of GDP, whereas four patients did not because they withdrew (n=1) or because they had an infection (n=3). The overall response rate and the CR rate were 90.6% (that is, 29 of 32 responses) and 84.4% (that is, 27 of 32 responses), respectively. Only two patient experienced grade 3 toxicity during CCRT (nausea), whereas 13 of the 30 patients experienced grade 4 neutropenia. The estimated 3-year overall survival and progression-free rates were 87.50% and 84.38%, respectively. In conclusion, CCRT followed by GDP chemotherapy can be a feasible and effective treatment strategy for stage IE to IIE nasal ENKTL.

Synthesis of carboxylic block copolymers via reversible addition fragmentation transfer polymerization for tooth erosion prevention

Dental professionals are seeing a growing population of patients with visible signs of dental erosion. The approach currently being used to address the problem typically leverages the enamel protection benefits of fluoride. In this report, an alternative new block copolymer with a hydrophilic polyacrylic acid (PAA) block and a hydrophobic poly(methyl methacrylate) (PMMA) block was developed to similarly reduce the mineral loss from enamel under acidic conditions. This series of PMMA-b-PAA block copolymers was synthesized by reversible addition fragmentation transfer (RAFT) polymerization. Their structures were characterized by gel permeation chromatography (GPC) and (1)H nuclear magnetic resonance (NMR) spectra. The molar fractions of acrylic acid (AA) in the final block copolymer were finely controlled from 0.25 to 0.94, and the molecular weight (Mn) of PMMA-b-PAA was controlled from 10 kDa to 90 kDa. The binding capability of the block copolymer with hydroxyapatite (HAP) was investigated by ultraviolet-visible spectroscopy (UV-Vis) and Fourier transform infrared (FTIR) spectroscopy. FTIR spectra confirmed that the PMMA-b-PAA block copolymer could bind to HAP via bridging bidentate bonds. Both UV-Vis and FTIR spectra additionally indicated that a high polymer concentration and low solution pH favored the polymer binding to HAP. The erosion-preventing efficacy of the PMMA-b-PAA block copolymer in inhibiting HAP mineral loss was quantitatively evaluated by atomic absorption spectroscopy (AAS). Based on the results, polymer treatment reduced the amount of calcium released by 27% to 30% in comparison with the unprotected samples. Scanning electron microscope (SEM) observations indicated that PMMA-b-PAA polymer treatment protected enamel from acid erosion. This new amphiphilic block copolymer has significant potential to be integrated into dentifrices or mouthrinses as an alternative non-fluoride ingredient to reduce tooth erosion.

A new variable for SRS plan quality evaluation based on normal tissue sparing: the effect of prescription isodose levels

OBJECTIVE

A new dosimetric variable, dose-dropping speed (DDS), was proposed and used to evaluate normal tissue sparing among stereotactic radiosurgery (SRS) plans with different prescription isodose lines.

METHODS

40 plans were generated for 8 intracranial SRS cases, prescribing to isodose levels (IDLs) ranging from 50% to 90% in 10% increments. Whilst maintaining similar coverage and conformity, plans at different IDLs were evaluated in terms of normal tissue sparing using the proposed DDS. The DDS was defined as the greater decay coefficient in a double exponential decay fit of the dose drop-off outside the planning target volume (PTV), which models the steep portion of the drop-off. Provided that the prescription dose covers the whole PTV, a greater DDS indicates better normal tissue sparing.

RESULTS

Among all plans, the DDS was found to be the lowest for the prescription at 90% IDL and the highest for the prescription at 60% or 70%. The beam profile slope change in the penumbra and its field size dependence were explored and given as the physical basis of the findings.

CONCLUSION

A variable was proposed for SRS plan quality evaluation. Using this measure, prescriptions at 60% and 70% IDLs were found to provide best normal tissue sparing.

ADVANCES IN KNOWLEDGE

A new variable was proposed based on which normal tissue sparing was quantitatively evaluated, comparing different prescription IDLs in SRS.

Associations of blood glucose and prevalent diabetes with risk of cardiovascular disease in 500 000 adult Chinese: the China Kadoorie Biobank

AIMS

To examine the relationship of self-reported diabetes, and of random blood glucose levels among individuals without known diabetes, with the prevalence of cardiovascular disease in Chinese adults.

METHODS

We examined cross-sectional data from the China Kadoorie Biobank of 0.5 million people aged 30-79 years recruited from 10 diverse regions of China in the period 2004-2008. Logistic regression was used to estimate the odds ratios of prevalent cardiovascular disease associated with self-reported diabetes, and with measured random blood glucose levels among participants with no history of diabetes, adjusting simultaneously for age, sex, area, education, smoking, alcohol, blood pressure and physical activity.

RESULTS

A total of 3.2% of participants had self-reported diabetes (men 2.9%; women 3.3%) and 2.8% had screen-detected diabetes (men 2.6%; women 2.8%), i.e. they had no self-reported history of diabetes but a blood glucose level suggestive of a diagnosis of diabetes. Compared with individuals without a history of diabetes, the odds ratios associated with self-reported diabetes were 2.18 (95% CI 2.06-2.30) and 1.88 (95% CI 1.75-2.01) for prevalent ischaemic heart disease and stroke/transient ischaemic attack, respectively. Among participants without self-reported diabetes there was a positive association between random blood glucose and ischaemic heart disease and stroke/transient ischaemic attack prevalence (P for trend <0.0001). Below the diabetic threshold (<11.1 mmol/l) each additional 1 mmol/l of random blood glucose was associated with 4% (95% CI 2-5%) and 5% (95% CI 3-7%) higher odds of prevalent ischaemic heart disease and stroke/transient ischaemic attack, respectively.

CONCLUSIONS

In this adult Chinese population, self-reported diabetes was associated with a doubling of the odds of prevalent cardiovascular disease. Below the threshold for diabetes there was still a modest, positive association between random blood glucose and prevalent cardiovascular disease.

Inhibition of ANKRD1 sensitizes human ovarian cancer cells to endoplasmic reticulum stress-induced apoptosis

High expression of Ankyrin Repeat Domain 1 (ANKRD1) in ovarian carcinoma is associated with poor survival, and in ovarian cancer cell lines is associated with platinum resistance. Importantly, decreasing ANKRD1 expression using siRNA increases cisplatin sensitivity. In this study, we investigated possible mechanisms underlying the association of ANKRD1 with cisplatin response. We first demonstrated that cisplatin-induced apoptosis in ovarian cancer cell lines was associated with endoplasmic reticulum (ER) stress, evidenced by induction of Glucose-Regulated Protein 78 (GRP78), growth arrest- and DNA damage-inducible gene 153 (GADD153) and increased intracellular Ca(2+) release. The level of sensitivity to cisplatin-induced apoptosis was associated with ANKRD1 protein levels and poly (ADP-ribose) polymerase (PARP) cleavage. COLO 316 ovarian cancer cells, which express high ANKRD1 levels, were relatively resistant to cisplatin, and ER stress-induced apoptosis, whereas OAW42 and PEO14 cells, which express lower ANKRD1 levels, are more sensitive to ER stress-induced apoptosis. Furthermore, we show that overexpression of ANKRD1 attenuated cisplatin-induced cytotoxicity, and conversely siRNA knockdown of ANKRD1 sensitized ovarian cancer cells to cisplatin and ER stress-induced apoptosis associated with induction of GADD153, and downregulation of BCL2 and BCL-XL. Taken together, these results suggest that ANKRD1 has a significant role in the regulation of apoptosis in human ovarian cancer cells, and is a potential molecular target to enhance sensitivity of ovarian cancer to chemotherapy.