A loop of cancer-stroma-cancer interaction promotes peritoneal metastasis of ovarian cancer via TNFα-TGFα-EGFR.

Peritoneum is the most common site for ovarian cancer metastasis. Here we investigate how cancer epigenetics regulates reciprocal tumor-stromal interactions in peritoneal metastasis of ovarian cancer. Firstly, we find that omental stromal fibroblasts enhance colony formation of metastatic ovarian cancer cells, and de novo expression of transforming growth factor-alpha (TGF-α) is induced in stromal fibroblasts co-cultured with ovarian cancer cells. We also observed an over-expression of tumor necrosis factor-alpha (TNF-α) in ovarian cancer cells, which is regulated by promoter DNA hypomethylation as well as chromatin remodeling. Interestingly, this ovarian cancer-derived TNF-α induces TGF-α transcription in stromal fibroblasts through nuclear factor-κB (NF-κB). We further show that TGF-α secreted by stromal fibroblasts in turn promotes peritoneal metastasis of ovarian cancer through epidermal growth factor receptor (EGFR) signaling. Finally, we identify a TNFα-TGFα-EGFR interacting loop between tumor and stromal compartments of human omental metastases. Our results therefore demonstrate cancer epigenetics induces a loop of cancer-stroma-cancer interaction in omental microenvironment that promotes peritoneal metastasis of ovarian cancer cells via TNFα-TGFα-EGFR.

Posterior ankle and hindfoot endoscopy: A cadaveric study.

BACKGROUND: The list of indications of posterior ankle endoscopy is expanding and includes various soft tissue and bony pathologies of the posterior ankle. Some of the indications, e.g. release of frozen ankle, debridement of posteromedial soft tissue impingement of the ankle and debridement or fixation of the posteromedial osteochondral lesion of the talus, require approach to the posterior ankle medial to the flexor hallucis longus tendon. The purpose of this study was to assess the risk of injury to the posterior tibial neurovascular bundle during posterior ankle endoscopy. METHODS: Fourteen fresh frozen foot and ankle specimens were used. A metal rod was inserted into the posteromedial, posterolateral and modified posteromedial portals and touched the medial border of the posterolateral talar tubercle and the posteromedial corner of the ankle mortise in turn. The neurovascular bundle and FHL tendon were examined for any kink. RESULTS: The neurovascular bundle was kinked in all specimens (100%) with the rod at the posteromedial corner of the ankle mortise through the posteromedial portal and was kinked in 11 specimens (79%) with the rod through the modified posteromedial portal. The neurovascular bundle was kinked in 1 specimen (7%) with the rod through the posterolateral portal. CONCLUSIONS: The neurovascular bundle was at risk during instrumentation of the posteromedial ankle through the posteromedial portal but was safe through the posterolateral portal.

The safety of the posterior ankle arthroscopy in management of posterior ankle impingement: A cadaveric study.

BACKGROUND: Arthroscopic management of the posterior ankle impingement with the patient in supine position has the advantage of dealing with anterior ankle pathology at the same time without the need to change position of the patient. This study aims at evaluation of the safety of portal establishment and instrumentation of this technique. METHODS: Sixteen fresh-frozen cadaver specimens were used. The relationships of the posteromedial and posterolateral portals to the adjacent tendons and nerves and the relationship of the coaxial portal tract with the posterior ankle capsule and the flexor hallucis longus tendon were studied. RESULT: Angle θ1 between the intermalleolar line and the posterior ankle coaxial portal tract averaged 1° (-10° to 22°). Angle θ2 between the intermalleolar line and the metal rod where the neurovascular bundle started to move averaged 19° (10° to 30°). Angle θ3 between the intermalleolar line and the metal rod where it reached the lateral border of the Achilles tendon was larger than angle θ2 in all specimens. The angle of safety (θs) averaged 18° (-1° to 26°). CONCLUSIONS: Injury to the tendon, nerves or vessels is possible during establishment of the portals and resection of the os trigonum.

G-quadruplex ligands exhibit differential G-tetrad selectivity.

A rapid and simple equilibrium-binding assay mediated by ligand-induced fluorescence quenching of fluorophore-labelled G-quadruplex (G4) structures enabled quantitative interrogation of mutually exclusive ligand binding interactions at opposed G-tetrads. This technique revealed that the ligands TmPyP4, PhenDC3, and PDS have differential chemotype-specific binding preferences for individual G-tetrads of a model genomic G4 structure.

Validation of the Chinese version of the dementia screening questionnaire for individuals with intellectual disabilities (DSQIID-CV).

BACKGROUND: An increasing number of people with intellectual disabilities (ID) are at risk of developing age-related disorders such as dementia because of a dramatic increase in life expectancy in this population in the recent years. There is no validated dementia screening instrument for Chinese people with ID. The Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID) was reported to be a valid, user-friendly, easy-to-use observer-rated instrument. It was developed in the UK and has good psychometric properties. Validation of a Chinese version of the DSQIID will facilitate its application among the Chinese population. METHOD: The DSQIID was translated into the Chinese version (DSQIID-CV). By purposive sampling, service users with ID aged 40 years or over were recruited through two large centres serving adults with ID in Hong Kong. Carers who had taken care of the participants continuously for the past 6 months were invited to complete the DSQIID-CV. All participants were examined by qualified psychiatrists to determine the presence or absence of dementia. RESULTS: Two hundred people with ID whose age ranged between 40 and 73 years (mean 51 years, SD=7.34 years) were recruited to the study. A clinical diagnosis of dementia was established in 13 participants. An overall total score of 22 as a screening cut-off provided the optimum levels of specificity (0.995) and sensitivity (0.923). The DSQIID-CV showed good internal consistency (alpha=0.945) for all its 53 items, and excellent test-retest reliability (0.978, n=46) and inter-rater reliability (1.000, n=47). Exploratory factor analysis resulted in a four-factor solution explaining 45% of the total variance. CONCLUSIONS: The DSQIID-CV is shown to have robust psychometric properties. It is the first valid and reliable dementia screening instrument for Chinese adults with ID.

Molecular classifiers for acute kidney transplant rejection in peripheral blood by whole genome gene expression profiling.

There are no minimally invasive diagnostic metrics for acute kidney transplant rejection (AR), especially in the setting of the common confounding diagnosis, acute dysfunction with no rejection (ADNR). Thus, though kidney transplant biopsies remain the gold standard, they are invasive, have substantial risks, sampling error issues and significant costs and are not suitable for serial monitoring. Global gene expression profiles of 148 peripheral blood samples from transplant patients with excellent function and normal histology (TX; n = 46), AR (n = 63) and ADNR (n = 39), from two independent cohorts were analyzed with DNA microarrays. We applied a new normalization tool, frozen robust multi-array analysis, particularly suitable for clinical diagnostics, multiple prediction tools to discover, refine and validate robust molecular classifiers and we tested a novel one-by-one analysis strategy to model the real clinical application of this test. Multiple three-way classifier tools identified 200 highest value probesets with sensitivity, specificity, positive predictive value, negative predictive value and area under the curve for the validation cohort ranging from 82% to 100%, 76% to 95%, 76% to 95%, 79% to 100%, 84% to 100% and 0.817 to 0.968, respectively. We conclude that peripheral blood gene expression profiling can be used as a minimally invasive tool to accurately reveal TX, AR and ADNR in the setting of acute kidney transplant dysfunction.

A novel miR-193a-5p-YY1-APC regulatory axis in human endometrioid endometrial adenocarcinoma.

Aberrant expression and altered function of transcription factors (TFs) have vital roles in many aspects of tumor development and progression. In this study, we investigated the functional significance of a TF, Yin Yang1 (YY1) in tumorigenesis of endometrioid endometrial carcinoma (EEC). We demonstrated that YY1 is upregulated in EEC cell lines and primary tumors; and its expression is associated with tumor stages. Depletion of YY1 inhibits EEC cell proliferation and migration both in vitro and in vivo, whereas overexpression of YY1 promotes EEC cell growth. These results suggest that YY1 functions as an oncogenic factor in EEC. Transcriptome analysis revealed a significant effect of YY1 on critical aspects of EEC tumorigenesis through inhibition of APC expression. Further mechanistic investigation uncovered a new epigenetic silencing mode of APC by YY1 through recruitment of EZH2 and trimethylation of histone 3 lysine 27 on its promoter region. Moreover, YY1 overexpression was found to be a consequence of miR-193a-5p downregulation through direct miR-193a-5p-YY1 interplay. Our results therefore establish a novel miR-193a-5p-YY1-APC axis, which contributes to EEC development, and may serve as future intervention target.

Krüppel-like factor 4 (KLF4) suppresses neuroblastoma cell growth and determines non-tumorigenic lineage differentiation.

Neuroblastoma (NB) is an embryonal tumor and possesses a unique propensity to exhibit either a spontaneous regression or an unrestrained growth. However, the underlying mechanism for this paradoxical clinical outcome remains largely unclear. Quantitative RT-PCR analysis on 102 primary NB tumors revealed that lower Krüppel-like factor 4 (KLF4) expression is frequently found in the unfavorable NB (Mann-Whitney test, P=0.027). In particular with the high-risk factors such as age of patient >1 year, MYCN amplification and low TRKA expression, the decreased expression of KLF4 was significantly associated with an unfavorable NB outcome. Despite knockdown of KLF4 alone is not sufficient to increase tumorigenicity of NB cells in vivo, stable expression of KLF4 short hairpin RNA in Be(2)-C cells significantly promoted growth of NB cells and inhibited cell differentiation toward fibromuscular lineage. In concordant with these observations, overexpression of KLF4 in SH-SY-5Y cells profoundly suppressed cell proliferation by direct upregulation of cell-cycle inhibitor protein p21(WAF1/CIP1), and knocking down p21(WAF1/CIP1) could partially rescue the suppressive effect of KLF4. Importantly, KLF4 overexpressing cells have lost their neuroblastic phenotypes, they were epithelial-like, strongly substrate-adherent, expressing smooth muscle marker and became non-tumorigenic, suggesting that KLF4 expression is crucial for lineage determination of NB cells, probably, favoring spontaneous tumor regression. Subsequent global gene expression profiling further revealed that transforming growth factor beta (TGFß) and cell-cycle pathways are highly dysregulated upon KLF4 overexpression, and myogenic modulators, MEF2A and MYOD1 were found significantly upregulated. Taken together, we have demonstrated that KLF4 contributes to the favorable disease outcome by directly mediating the growth and lineage determination of NB cells.

The strength/weakness of the AJCC/UICC staging system (7th edition) for nasopharyngeal cancer and suggestions for future improvement.

BACKGROUND AND PURPOSE: To evaluate the current AJCC/UICC staging system (7th edition) for nasopharyngeal carcinoma and to explore for future improvement. MATERIALS AND METHODS: A total of 985 patients, initially staged with preceding 5-6th edition, were retrospectively re-staged with the 7th edition. All were assessed by magnetic resonance imaging, and all 945 non-disseminated patients were irradiated with conformal/intensity-modulated technique. RESULTS: Staging factors by both the 5-6th edition and the 7th edition were strongly significance for important endpoints (p<0.001). Down-staging of the previous T2a to T1 and, stages IIA to I in the 7th edition was appropriate. However, the impacts on overall stage distribution and prognostication were minimal. Further down-staging of the current T2 to T1, N2 to N1, stages II to I, and merging of N3a and N3b, stages IVA and IVB were suggested. With the 7th edition, the 5-year disease-specific survival (DSS) was 100% for stage I, 95% for II, 90% for III, 67% for IVA, 68% for IVB and 18% for IVC. The corresponding DSS for the proposed stages I, II, III and IV were 95%, 86%, 67% and 18%, respectively. CONCLUSIONS: The changes introduced in the 7th edition were appropriate, but the magnitude of improvement was minimal. With improving results by modern management, further simplification of the staging system is suggested. The proposed system could lead to more accurate prognostication, further validation is warranted.

Nasopharyngeal carcinoma: salvage of local recurrence.

Local control of nasopharyngeal carcinoma has substantially improved with advancing radiotherapy technology and appropriate combination with chemotherapy. However, when local recurrence occurs, this is one of the most difficult challenges. Aggressive treatment is indicated because long term salvage is achievable particularly for early recurrence, but high risk of complications is a serious concern. Treatment options include different methods of surgery and/or re-irradiation with/without chemotherapy. Available information in the literature is grossly inadequate; most reports compose of small series of highly selected patients with heterogeneous characteristics and treatment. No randomized trials have been performed to evaluate the therapeutic ratio of different treatment methods. This article reviews available treatment options, their therapeutic benefits and risks of complications; the objective is to provide information for developing treatment recommendations and suggestions for future improvement.

Self-perceived preparedness for dental practice amongst graduates of The University of Hong Kong's integrated PBL dental curriculum.

OBJECTIVES: To determine how prepared for dental practice graduates from the integrated problem-based learning (PBL) dental undergraduate curriculum at The University of Hong Kong (HKU) perceive themselves to be and to identify factors associated with self-perceived preparedness. MATERIALS AND METHODS: A postal questionnaire was sent to five cohorts of dentists who had graduated from HKU's integrated PBL curriculum between 2004 and 2008. Using a 4-point Likert scale, the questionnaire assessed the self-perceived level of preparedness in 59 competencies grouped in nine domains. Responses were dichotomised into 'poorly prepared' and 'well prepared'. RESULTS: The response rate was 66% (159/241). The mean proportion (±standard deviation) of respondents indicating well-preparedness was 72.0±15.1% overall, and for each domain was as follows: general patient management, 93.1±12.1%; practice management, 81.0±22.2%; periodontology and dental public health, 73.5±19.3%; conservative dentistry, 92.5±13.1%; oral rehabilitation, 62.8±24.0%; orthodontics, 23.0±32.9%; managing children and special-needs patients, 64.8±28.9%; oral and maxillofacial surgery, 52.2±25.2%; and drug and emergency management, 84.7±22.6%. The odds of self-perceived well-preparedness were increased for cohorts graduating in 2004 and 2005 and graduates working in a non-solo dental practice. CONCLUSIONS: Dental graduates of HKU's integrated PBL curriculum felt well prepared for the most fundamental aspects of dental practice. However, apparent deficiencies of training in orthodontics and oral and maxillofacial surgery will need to be addressed by continuing education, postgraduate training and planning for the new 6-year undergraduate curriculum in 2012.

Dysregulation of microRNA-204 mediates migration and invasion of endometrial cancer by regulating FOXC1.

MicroRNAs (miRNAs) regulate mRNA stability and protein expression, and certain miRNAs have been demonstrated to act either as oncogenes or tumor suppressors. Differential miRNA expression signatures have been documented in many human cancers but the role of miRNAs in endometrioid endometrial cancer (EEC) remains poorly understood. This study identifies significantly dysregulated miRNAs of EEC cells, and characterizes their impact on the malignant phenotype. We studied the expression of 365 human miRNAs using Taqman low density arrays in EECs and normal endometriums. Candidate differentially expressed miRNAs were validated by quantitative real-time PCR. Expression of highly dysregulated miRNAs was examined in vitro through the effect of anti-/pre-miRNA transfection on the malignant phenotype. We identified 16 significantly dysregulated miRNAs in EEC and 7 of these are novel findings with respect to EEC. Antagonizing the function of miR-7, miR-194 and miR-449b, or overexpressing miR-204, repressed migration, invasion and extracellular matrix-adhesion in HEC1A endometrial cancer cells. FOXC1 was determined as a target gene of miR-204, and two binding sites in the 3'-untranslated region were validated by dual luciferase reporter assay. FOXC1 expression was inversely related to miR-204 expression in EEC. Functional analysis revealed the involvement of FOXC1 in migration and invasion of HEC1A cells. Our results present dysfunctional miRNAs in endometrial cancer and identify a crucial role for miR-204-FOXC1 interaction in endometrial cancer progression. This miRNA signature offers a potential biomarker for predicting EEC outcomes, and targeting of these cancer progression- and metastasis-related miRNAs offers a novel potential therapeutic strategy for the disease.

Graduates' perceived preparedness for dental practice from PBL and traditional curricula.

The objective of this study was to compare dental graduates' perceived preparedness for practice after being educated in a problem-based learning (PBL) curriculum with those who graduated from a traditional undergraduate curriculum, both at the University of Hong Kong. A cohort of graduates from the traditional dental curriculum (1997-2001) and a cohort of graduates from the PBL curriculum (2004-08) rated their self-perceived preparedness for dental practice in fifty-nine aspects of dentistry across nine domains. Perceived preparedness for dental practice was compared at domain and item levels (accounting for multiple comparisons) using chi-square statistics. Both cohorts felt well prepared for the "bread and butter" aspects of dentistry, but less so for specific specialty disciplines. There was no significant difference between PBL and traditional graduates' self-perceived preparedness in eight of the nine domains of dental practice (P>0.05). However, in the area of orthodontics, both cohorts felt ill-prepared for practice and more so among the PBL cohort (P<0.01). For the most part, regardless of curriculum design, these dental graduates perceived themselves to be well prepared for dental practice.

Learning needs in a medical curriculum in Hong Kong.

OBJECTIVE: To survey medical graduates from the University of Hong Kong on how well they perceived their learning needs had been fulfilled by the old (before 1997) and the new (after 1997) curricula. DESIGN: Retrospective questionnaire survey. SETTING: The University of Hong Kong, Hong Kong. PARTICIPANTS: Medical graduates from the University of Hong Kong who graduated between 1997 and 2006 were invited to complete a questionnaire online or in paper form; 1997-2001 graduates were trained under the old curriculum, and 2002-2006 graduates under the new curriculum. RESULTS: The response rate was 23%. The survey showed that the graduates of both curricula felt that research skills, population health, and ophthalmology were not emphasised enough in the medical programme. In addition, some graduates of the old curriculum mentioned interpersonal skills, ethics and professionalism, and language skills, which were pinpointed in the curriculum reform in 1997. Some graduates of the new curriculum mentioned anatomy, microbiology, and diagnostic radiology. Graduates of both the old and the new curricula perceived the same top five areas as being lacking in their respective curricula, in relationship to their clinical career and personal growth, namely: business administration, law, professional English, life coaching, and humanities. A small percentage of graduates also took courses in these areas after graduation. CONCLUSIONS: The survey showed that the curriculum reform in 1997 at the University of Hong Kong had correctly pinpointed some of the learning needs. The survey also identified educational needs in the existing curriculum that need to be dealt with in the forthcoming curriculum reform in 2012.

Factors contributing to the efficacy of concurrent-adjuvant chemotherapy for locoregionally advanced nasopharyngeal carcinoma: combined analyses of NPC-9901 and NPC-9902 Trials.

BACKGROUND: The current standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC) was conventional-fractionation radiotherapy plus concurrent-adjuvant chemotherapy as recommended by the Intergroup-0099 Study. This combined analysis of the NPC-9901 and the NPC-9902 Trials aims to provide more comprehensive data to evaluate the efficacy of the Intergroup-0099 regimen and the contributing factors. METHODS: Eligible patients with stage III-IVB non-keratinizing NPC were randomly assigned to radiotherapy-alone (RT(i) group: 218 patients) or chemoradiotherapy (CRT(i) group: 223 patients) using cisplatin (100mg/m(2)) for three cycles in concurrence with radiotherapy, followed by cisplatin (80 mg/m(2)) plus fluorouracil (1000 mg/m(2)/day for 4 days) for three cycles. The median follow-up was 6.1 years. FINDINGS: Comparison by intention-to-treat showed that the CRT(i) group achieved significant improvement in overall failure-free rate (FFR), locoregional-FFR and cancer-specific survival (p ≤ 0.019); but the improvements for distant-FFR and overall survival (OS) were statistically insignificant (p ≥ 0.14). Further exploratory studies based on actual treatment showed that an additional improvement achieved was a significant gain in OS (CRT(a) versus RT(a) group: 72% versus 63% at 5-year, p=0.037). Multivariate analyses showed that the dose of cisplatin during the concurrent phase had significant impact on locoregional-FFR and OS, while that of fluorouracil during the adjuvant phase was significant for distant-FFR. The 5-year locoregional-FFR for patients who received 0-1, 2 and 3 concurrent cycles were 79%, 88% and 88%, respectively; the corresponding distant-FFR by adjuvant cycles were 68%, 78% and 77%, respectively. INTERPRETATION: Our results support the current practice of adding concurrent cisplatin plus adjuvant cisplatin-fluorouracil to radiotherapy for treating patients with locoregionally advanced NPC. The concurrent phase is important for locoregional control and survival, cisplatin 200mg/m(2) in two concurrent cycles might be adequate. Additional chemotherapy using fluorouracil-containing combination contributed to improving distant control.

Effects of abiotic stress on biomass and anthocyanin production in cell cultures of Melastoma malabathricum.

Plant cell cultures could be used as an important tool for biochemical production, ranging from natural coloring (pigments) to pharmaceutical products. Anthocyanins are becoming a very important alternative to synthetic dyes because of increased public concern over the safety of artificial food coloring agents. Several factors are responsible for the production of anthocyanin in cell cultures. In the present study, we investigate the effects of different environmental factors, such as light intensity, irradiance (continuous irradiance or continuous darkness), temperature and medium pH on cell biomass yield and anthocyanin production in cultures of Melastoma malabathricum. Moderate light intensity (301 - 600 lux) induced higher accumulation of anthocyanins in the cells. The cultures exposed to 10-d continuous darkness showed the lowest pigment content, while the cultures exposed to 10-d continuous irradiance showed the highest pigment content. The cell cultures incubated at a lower temperature range (20 ± 2 ºC) grew better and had higher pigment content than those grown at 26 ± 2 ºC and 29 ± 2 ºC. Different medium pH did not affect the yield of cell biomass but anthocyanin accumulation was highest at pH 5.25 - 6.25.

Modified plantar plate tenodesis for correction of claw toe deformity.

BACKGROUND: The purpose of the study was to evaluate the efficacy and safety of the modified plantar plate tenodesis for correction of claw toe deformity. MATERIALS AND METHODS: Modified plantar plate tenodesis was performed in ten fresh frozen cadaveric feet with claw toe deformity of the second toe. The plantar plate of the second metatarsophalangeal joint was anchored to the extensor digitorum longus tendon by a figure-of-eight suture. The figure-of-eight construct and the relationship of the digital nerve and the suture were studied. A clinical study was conducted to study the operative times, degree of correction and the improvement of AOFAS score between groups with the original plantar plate tenodesis (Group 1) and modified technique (Group 2). Any neural injury if present was also noted. RESULT: In the cadaveric study, the claw toe deformity was corrected and no nerve injury occurred in any specimen. There was flexor tendon tethering by the suture in 2 specimens. In the clinical study, the average operative time was 51 minutes for Group 1 and 31 minutes for Group 2. The improvement in AOFAS score averaged 44 in Group 1 and 43 in Group 2. The corrective power of the sagittal plane deformity at the metatarsophalangeal joint averaged 25 degrees in Group 1 and 23 degrees in Group 2. CONCLUSION: Plantar plate tenodesis was effective in correction of flexible claw second toe deformity by stabilization of the attenuated plantar plate. The modified technique allowed easier retrieval of the suture and shorter operative time. However, it may result in tethering of the flexor tendon.

Body image and the breast: the psychological wound.

Breast reconstruction or cosmetic surgery inevitably results in an altered body image. An awareness of the effects of such surgery on the patient's body image, and thus quality of life, is as important as treating the physiological wound.