ARCHITECTURAL PATTERNS FOR DIFFERENTIAL DIAGNOSIS OF PROLIFERATIVE BREAST LESIONS FROM HISTOPATHOLOGICAL IMAGES.

The differential diagnosis of proliferative breast lesions, benign usual ductal hyperplasia (UDH) versus malignant ductal carcinoma in situ (DCIS) is challenging. This involves a pathologist examining histopathologic sections of a biopsy using a light microscope, evaluating tissue structures for their architecture or size, and assessing individual cell nuclei for their morphology. Imposing diagnostic boundaries on features that otherwise exist on a continuum going from benign to atypia to malignant is a challenge. Current computational pathology methods have focused primarily on nuclear atypia in drawing these boundaries. In this paper, we improve on these approaches by encoding for both cellular morphology and spatial architectural patterns. Using a publicly available breast lesion database consisting of UDH and three different grades of DCIS, we improve the classification accuracy by 10% over the state-of-the-art method for discriminating UDH and DCIS. For the four way classification of UDH and the three grades of DCIS, our method improves the results by 6% in accuracy, 8% in micro-AUC, and 19% in macro-AUC.

Functional interaction of histone deacetylase 5 (HDAC5) and lysine-specific demethylase 1 (LSD1) promotes breast cancer progression.

We have previously demonstrated that crosstalk between lysine-specific demethylase 1 (LSD1) and histone deacetylases (HDACs) facilitates breast cancer proliferation. However, the underlying mechanisms are largely unknown. Here, we report that expression of HDAC5 and LSD1 proteins were positively correlated in human breast cancer cell lines and tissue specimens of primary breast tumors. Protein expression of HDAC5 and LSD1 was significantly increased in primary breast cancer specimens in comparison with matched-normal adjacent tissues. Using HDAC5 deletion mutants and co-immunoprecipitation studies, we showed that HDAC5 physically interacted with the LSD1 complex through its domain containing nuclear localization sequence and phosphorylation sites. Although the in vitro acetylation assays revealed that HDAC5 decreased LSD1 protein acetylation, small interfering RNA (siRNA)-mediated HDAC5 knockdown did not alter the acetylation level of LSD1 in MDA-MB-231 cells. Overexpression of HDAC5 stabilized LSD1 protein and decreased the nuclear level of H3K4me1/me2 in MDA-MB-231 cells, whereas loss of HDAC5 by siRNA diminished LSD1 protein stability and demethylation activity. We further demonstrated that HDAC5 promoted the protein stability of USP28, a bona fide deubiquitinase of LSD1. Overexpression of USP28 largely reversed HDAC5-KD-induced LSD1 protein degradation, suggesting a role of HDAC5 as a positive regulator of LSD1 through upregulation of USP28 protein. Depletion of HDAC5 by shRNA hindered cellular proliferation, induced G1 cell cycle arrest, and attenuated migration and colony formation of breast cancer cells. A rescue study showed that increased growth of MDA-MB-231 cells by HDAC5 overexpression was reversed by concurrent LSD1 depletion, indicating that tumor-promoting activity of HDAC5 is an LSD1 dependent function. Moreover, overexpression of HDAC5 accelerated cellular proliferation and promoted acridine mutagen ICR191-induced transformation of MCF10A cells. Taken together, these results suggest that HDAC5 is critical in regulating LSD1 protein stability through post-translational modification, and the HDAC5-LSD1 axis has an important role in promoting breast cancer development and progression.

Pattern of c-fos mRNA induction in rat brain by acute morphine.

Initially, opioid signaling had been thought to be mainly inhibitory in nature. However, it has been shown that opioids can activate specific signaling pathways and induce immediate early gene (IEG) transcription in brain. IEGs can then regulate the transcription of other genes, leading to changes in neuronal function in response to extracellular stimuli. This study was designed to identify brain regions that demonstrate specific induction of the IEG c-fos, a component of the AP-1 transcription factor, in response to acute morphine, and to contrast this induction with the stressful effects of the injection itself. Rats received either 10 mg/kg morphine or an equivalent volume of saline injected subcutaneously. Animals were then sacrificed 15, 30, or 60 min after injection. Specific induction of c-fos mRNA by morphine was seen in dorsomedial caudate-putamen, paraventricular nucleus of the thalamus, central and intralaminar thalamic nuclei, dorsal central grey, superior colliculus, lateral parabrachial nucleus, inferior olivary complex, and caudal nucleus tractus solitarius. These findings represent the first complete anatomical mapping of c-fos induction in rat brain, and show that acute morphine administration alters gene expression in several areas related to known functional properties of opioids. However, regions showing c-fos induction are not all classically associated with opioid receptors and opioid-mediated effects. These findings are considered in the context of the effects of opioids on neural circuitry as well as direct, receptor-mediated effects of morphine on neural cells.

Key residues defining the mu-opioid receptor binding pocket: a site-directed mutagenesis study.

Structural elements of the rat mu-opioid receptor important in ligand receptor binding and selectivity were examined using a site-directed mutagenesis approach. Five single amino acid mutations were made, three that altered conserved residues in the mu, delta, and kappa receptors (Asn150 to Ala, His297 to Ala, and Tyr326 to Phe) and two designed to test for mu/delta selectivity (Ile196 to Val and Val202 to Ile). Mutation of His297 in transmembrane domain 6 (TM6) resulted in no detectable binding with [3H]DAMGO (3H-labeled D-Ala2, N-Me-Phe4, Gly-ol5-enkephalin), [3H]bremazocine, or [3H]ethylketocyclazocine. Mutation of Asn150 in TM3 produces a three- to 20-fold increase in affinity for the opioid agonists morphine, DAMGO, fentanyl, beta-endorphin1-31, JOM-13, deltorphin II, dynorphin1-13, and U50,488, with no change in the binding of antagonists such as naloxone, naltrexone, naltrindole, and nor-binaltorphamine. In contrast, the Tyr326 mutation in TM7 resulted in a decreased affinity for a wide spectrum of mu, delta, and kappa agonists and antagonists. Altering Val202 to Ile in TM4 produced no change on ligand affinity, but Ile196 to Val resulted in a four- to fivefold decreased affinity for the mu agonists morphine and DAMGO, with no change in the binding affinities of kappa and delta ligands.

Prescribing efficiently in nursing homes.

Giving medications in nursing homes is time consuming and expensive. The orders for medications in a community nursing home were examined to determine if nursing time could be saved by consolidating the administration of medications. Nineteen percent of the medication administration visits could be eliminated by this method according to the independent judgments of two physicians. This could save up to $19,000 in nursing time per year, and the time could be redirected to other nursing activities that could improve the quality of care in nursing homes.