Proliferation-associated POU4F2/Brn-3b transcription factor expression is regulated by oestrogen through ERα and growth factors via MAPK pathway.

INTRODUCTION: In cancer cells, elevated transcription factor-related Brn-3a regulator isolated from brain cDNA (Brn-3b) transcription factor enhances proliferation in vitro and increases tumour growth in vivo whilst conferring drug resistance and migratory potential, whereas reducing Brn-3b slows growth both in vitro and in vivo. Brn-3b regulates distinct groups of key target genes that control cell growth and behaviour. Brn-3b is elevated in >65% of breast cancer biopsies, but mechanisms controlling its expression in these cells are not known. METHODS: Bioinformatics analysis was used to identify the regulatory promoter region and map transcription start site as well as transcription factor binding sites. Polymerase chain reaction (PCR) cloning was used to generate promoter constructs for reporter assays. Chromatin immunoprecipitation and site-directed mutagenesis were used to confirm the transcription start site and autoregulation. MCF-7 and Cos-7 breast cancer cells were used. Cells grown in culture were transfected with Brn-3b promoter and treated with growth factors or estradiol to test for effects on promoter activity. Quantitative reverse transcriptase PCR assays and immunoblotting were used to confirm changes in gene and protein expression. RESULTS: We cloned the Brn-3b promoter, mapped the transcription start site and showed stimulation by estradiol and growth factors, nerve growth factor and epidermal growth factor, which are implicated in breast cancer initiation and/or progression. The effects of growth factors are mediated through the mitogen-activated protein kinase pathway, whereas hormone effects act via oestrogen receptor α (ERα). Brn-3b also autoregulates its expression and cooperates with ERα to further enhance levels. CONCLUSIONS: Key regulators of growth in cancer cells, for example, oestrogens and growth factors, can stimulate Brn-3b expression, and autoregulation also contributes to increasing Brn-3b in breast cancers. Since increasing Brn-3b profoundly enhances growth in these cells, understanding how Brn-3b is increased in breast cancers will help to identify strategies for reducing its expression and thus its effects on target genes, thereby reversing its effects in breast cancer cells.

Heat perfusion for malignancy.

Hyperthermia, total anoxia and low pH have shown selective lethal effect on malignant cells. A perfusion system was devised to combine these modalities and was tried in 4 cases of advanced malignancy. A perfusion lasting for 45 minutes was found safe for normal tissue and yet selectively injurious to malignant cells. Technically this is a very simple procedure and its principles can be utilized in regional infusion also. Though the clinical material is scanty,the method deserves further trial.

Prenatal diagnosis of ventriculocoronary arterial communication in fetuses with hypoplastic left heart syndrome.

OBJECTIVE: The purpose of this series was to describe the fetal echocardiographic findings in hypoplastic left heart syndrome with aortic atresia and ventriculocoronary arterial communication and implications of these findings. METHODS: We describe 2 fetuses with hypoplastic left heart syndrome with ventriculocoronary arterial communication diagnosed at 29 and 20 weeks' gestation, respectively. The underlying cardiac anatomy consisted of a hypoplastic left heart and mitral stenosis with aortic atresia. We used color Doppler and pulsed Doppler sonography on the surface of the myocardium to specifically look for coronary arterial flow. RESULTS: By color Doppler sonography, ventriculocoronary arterial communication was shown between the left ventricular cavity and the left coronary artery with characteristic bidirectional flow on pulsed Doppler examination. There was no mitral regurgitation. The left ventricular myocardium was substantially hypertrophied. The first patient underwent surgical Norwood palliation and died after a prolonged postoperative course. The second patient underwent stenting of the arterial duct and bilateral pulmonary artery banding in the catheterization laboratory but died after a few weeks. Implications of ventriculocoronary arterial communication in association with hypoplastic left heart syndrome are discussed. CONCLUSIONS: It is possible to accurately diagnose ventriculocoronary arterial communication on fetal echocardiography. The presence of ventriculocoronary arterial communication is seen exclusively in a subgroup of patients with an aortic atresia and mitral stenosis variant of hypoplastic left heart syndrome. The prognosis is poor in this subgroup of patients.

Totally anomalous pulmonary venous connection and complex congenital heart disease: prenatal echocardiographic diagnosis and prognosis.

OBJECTIVE: The purpose of this study was to determine the accuracy of prenatal cardiac diagnosis, prognosis, and outcome of totally anomalous pulmonary venous connection (TAPVC) and to determine echocardiographic clues in the prenatal diagnosis of isolated TAPVC or TAPVC in association with other complex congenital heart disease (CHD). METHODS: We reviewed our 13-year experience of prenatal diagnosis of TAPVC. Thirteen fetuses were identified with the diagnoses of TAPVC. We systematically analyzed the individual pulmonary veins by color and pulsed Doppler imaging, the presence of a pulmonary venous confluence, the pulsed and color Doppler evaluation of the vertical vein, and sites of connections. Prenatal diagnosis was confirmed by postnatal echocardiography, cardiac catheterization, surgery, or autopsy. RESULTS: The mean gestational age at diagnosis of TAPVC was 26.3 weeks (range, 20-33 weeks). There were 8 fetuses with TAPVC and right isomerism, 3 fetuses with other associated CHD, and 2 with isolated TAPVC. There were 7 fetuses with supracardiac TAPVC, 4 with infracardiac TAPVC, and 2 with mixed TAPVC. Pulmonary vein color and pulsed Doppler data were available in 10 of 13 fetuses. The pulmonary venous confluence was visualized in all fetuses except 1. The vertical vein was visualized in all fetuses. Five fetuses had suspected signs of obstruction. The diagnosis was confirmed postnatally or at autopsy in 12 cases. Eight patients underwent surgery; 6 died, and 2 were alive. Two patients had compassionate care and died; 3 pregnancies were terminated. CONCLUSIONS: It is possible to diagnose accurately complex CHD, including the pulmonary venous connections. When diagnosed prenatally, TAPVC carries a poor prognosis.

Expression of the Brn-3b transcription factor correlates with expression of HSP-27 in breast cancer biopsies and is required for maximal activation of the HSP-27 promoter.

In breast cancer, overexpression of the small heat shock protein, HSP-27, is associated with increased anchorage-independent growth, increased invasiveness, and resistance to chemotherapeutic drugs and is associated with poor prognosis and reduced disease-free survival. Therefore, factors that increase the expression of HSP-27 in breast cancer are likely to affect the prognosis and outcome of treatment. In this study, we show a strong correlation between elevated levels of the Brn-3b POU transcription factor and high levels of HSP-27 protein in manipulated MCF-7 breast cancer cells as well as in human breast biopsies. Conversely, HSP-27 is decreased on loss of Brn-3b. In cotransfection assays, Brn-3b can strongly transactivate the HSP-27 promoter, supporting a role for direct regulation of HSP-27 expression. Brn-3b also cooperates with the estrogen receptor (ER) to facilitate maximal stimulation of the HSP-27 promoter, with significantly enhanced activity of this promoter observed on coexpression of Brn-3b and ER compared with either alone. RNA interference and site-directed mutagenesis support the requirement for the Brn-3b binding site on the HSP-27 promoter, which facilitates maximal transactivation either alone or on interaction with the ER. Chromatin immunoprecipitation provides evidence for association of Brn-3b with the HSP-27 promoter in the intact cell. Thus, Brn-3b can, directly and indirectly (via interaction with the ER), activate HSP-27 expression, and this may represent one mechanism by which Brn-3b mediates its effects in breast cancer cells.

HLHS with severe aortic insufficiency in a patient with 45,X/46,XY mosaicism.

Aortic insufficiency is not a part of the hypoplastic left heart syndrome. This report describes a rare case of congenital aortic insufficiency from a detached leaflet in a patient with hypoplastic left heart syndrome and 45,X/46XY mosaicism. The patient was subsequently treated with the modified Norwood procedure along with suture closure of aortic valve.

Role of mitotic counts in the grading and prognosis of the breast cancer.

100 Cases of invasive breast cancer were studied for Tumor type, Tumor site, Nodal Status, Mitotic counts, Nuclear pleomorphism, Tubule formation and Nottingham modification of Bloom Richardson Grading. The follow up of the 82 patients treated with surgery and adjuvant treatment was available. Mitotic activity index (MAI) counted with strict criteria of elston CW, emerged as one of the most significant prognostic parameter followed by overall grade in predicting Tumor free survival (TFS) for the patients. Mitotic count also correlated well with overall Grade and lymph node status in predicting the TFS. This parameter is very useful where advanced studies like flowcytometry and immunohistochemical studies of the cell proliferation marker are not available.