Abstract
BackgroundBreast cancer is a collection of molecularly distinct neoplastic diseases and therefore, we hypothesized that p53 gene mutations may lead to different transcriptional changes in ...the different molecular subtypes and these may translate into subtype-dependent prognostic and predictive values.MethodsWe developed gene expression-based predictors of p53 status separately for estrogen receptor-positive (ER+) and -negative (ER-) breast cancers from a publicly available data set with known p53 mutation status (n=251). We validated the two signatures on an independent cohort of cancers (n=103) with known p53 functional status and tested their prognostic and predictive values on two other cohorts of breast cancers that received no systemic adjuvant therapy (n=255; n=198), and on one cohort of ER+ patients treated with adjuvant tamoxifen (n=277). We also examined if the p53 signatures were associated with chemotherapy sensitivity in ER+ and ER- cancers, respectively in two separate neoadjuvant data sets (n=233; n=103).ResultsWe developed a 39-gene p53 signature derived from 213 ER+ and a 30-gene p53 signature derived from 38 ER- breast cancers with no overlapping genes. External validation showed a sensitivity and specificity of 89% and 54%, respectively for the 39-gene signature in ER+ breast cancers; and 82% and 61%, respectively for the 30-gene signature in ER- cancers. The 39-gene signature was predictive of worse distant metastasis free survival (DMFS) in ER+ cancers with p53 dysfunction in both prognostic data sets (Hazard ratio (HR): 2.3 (95% confidence interval (CI):1.25-4.23, p=0.005 and HR:2.17 (95%CI:0.85-5.56, p=0.09). It remained predictive of worse DMFS even after tamoxifen adjuvant therapy (HR=2.43, 95%CI: 1.35-4.38, p<0.0001). In contrast it was associated with higher chemotherapy sensitivity in ER+ cancers. Its predictive accuracy for pathologic complete response was of 68% (95%CI: 64-70%), sensitivity 89% (95%CI: 58-98%), specificity 67% (95%CI: 65-68%), positive predictive value 15% (95%CI: 10-17%), and negative predictive value 99% (95%CI: 96-100%) in ER+ cancers. The prognostic and predictive values remained significant in multivariate analysis. The same 39-gene signature was not prognostic or predictive in ER- cancers. The 30-gene signature derived from ER- tumors had no chemotherapy response predictive value in either ER- or ER+ cancers. The p53 dysfunctional cases showed better survival in the absence of any adjuvant therapy among ER- cancers. It had no prognostic value in ER+ cancers.ConclusionThese observations support the hypothesis that predictive or prognostic biomarkers may be best developed separately for different clinical and molecular subsets of breast cancer. P53 dysfunction is clinically most relevant in ER+ breast cancers.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6122.
The signal delivery pathway triggered by crosslinking CD3 and Thy-1 together (CD3/Thy-1 crosslinkage) on murine thymocytes for cellular DNA fragmentation/growth inhibition was analyzed. The treatment ...of thymocytes with herbimycin A as a specific tyrosine kinase inhibitor under suboptimum conditions before the CD3/Thy-1 crosslinkage partially but preferentially inhibited the otherwise promoted tyrosine phosphorylation of p40 and p56. Evidence was then provided that acceleration of the kinase activity of p56lck was involved in the CD3/Thy-1 crosslinkage-triggered signal. Partial characterization of p40 distinguished it from the p43 and p41 MAP kinases, the tyrosine phosphorylation of which was only marginally accelerated. Promotion of DNA fragmentation by the CD3/Thy-1 crosslinkage-triggered signal was actually ablated by the treatment with herbimycin, suggesting the obligatory involvement of the herbimycin highly sensitive kinase activity in the signal pathway. The signal induced by co-crosslinkage of CD3 and Thy-1 was also shown to be negatively biased against mature T lymphocytes, suppressing their CD3-mediated growth response. The negative signal was then found to partially attack the process of c-fos transcription as an earlier nuclear event. Interestingly, this c-fos suppression was prevented by the treatment of thymocytes with herbimycin before stimulation, for accelerated expression of c-fos. It is suggested from these results that the CD3/Thy-1 crosslinkage delivers protein tyrosine kinase-dependent negative signaling for inhibition of early and late nuclear events of both immature thymocytes and mature T lymphocytes.
To estimate the usefulness of the bedside swallowing assessment proposed by Smithard et al and neuroimaging findings characteristic for dysphagia, we studied the outcome of 102 patients with chronic ...cerebral infarction after assessment of swallowing by this test with brain computerized tomography (CT). All patients had a variety of motor disturbance and were admitted on a long-term medicare basis. They were divided into two groups according to the findings: the positive group (n=33), who showed any of the listed types of difficulty in swallowing water, and the negative group (n=69). Followed up to 2.2 years, their outcomes were studied. CT findings were studied on type of infarction, number and laterality of infarction, grade of periventricular lucency (PVL), presence of ventricular dilatation (VD), and severity of cortical atrophy (CA). The mean age was 76.4 years at registration and 61 were men. The frequency of severe dementia and disturbed ADL were significantly higher in the positive group. Eighteen patients died during the observation period and 15 of those were in the positive group, indicating higher annual death rate (29.9% vs 2.2% in the negative group). All of the 15 patients in the positive group died of pneumonia. CT findings showed high incidence of multiple infarction, bilateral hemispheric lesion, severe PVL, VD, and severe CA in the positive group. These findings indicated that this evaluation method was useful in screening swallow function for patients with cerebral infarction in the chronic phase. Furthermore, CT findings suggested that severe white matter lesion, VD, and severe CA as well as multiple infarction seen in bilateral hemisphere was related to dysphagia, probably due to multiple factors involving pyramidal- and extrapyramidal-tracts with higher brain function.
To clarify the factors influencing platelet function in elderly patients with chronic thrombotic disease, platelet aggregability was studied in 839 blood samples from 497 patients with a variety of ...diseases. Clinical stage (thrombotic disease), vascular risk factors, and data concerning any administration of antiplatelet drugs were assessed, as well as brain computerized tomographic and carotid ultrasonographic findings. Platelet aggregability was determined spectrophotometrically with an aggregometer (PAM-8T) and adenosine-5'-diphosphate as an agonist to determine new parameters: the grading curve (GC) type, and platelet aggregability threshold index (PATI). Multiple regression analysis showed that the antiplatelet therapy greatly influenced the GC type. Platelet aggregability, which accelerated with aging, was strongly suppressed by ticlopidine. Furthermore, excluding samples with antiplatelet therapy, statistical analysis showed that platelet aggregability was accelerated in women, and in patients with bilateral or complicated carotid lesions, although these patients were significantly older than the others. These findings suggested that accelerated aggregability in the elderly substantially reflected the progress of arteriosclerosis with age. Moreover, the findings indicated that the determination of GC type and PATI were useful in monitoring elderly patients recieving antiplatelet therapy, especially with ticlopidine.
To clarify the present status and problems in medical care for the elderly with dementia, 103 cases were studied according to the descriptive records obtained at a public counselling facility for ...dementia, based on interviews with patients' families. Their records were analysed based on their background, severity of dementia (clinical dementia rating: CDR), and counselling content. There were 75 demented patients with a CDR score of 1 or more, and 50 of them were women aged 54 to 90, while the remaining 25 men were aged 55 to 88. The consultation content was clustered into 5 codes: code 1, evaluation of dementia and/or dementia-related symptoms including psychiatric symptoms and behavioral disturbance; code 2, methods to manage patients; code 3, methods to take a patient to a medical institution; code 4, questions regarding medical treatment and drugs prescribed at present; code 5, information on the welfare resources provided. In most of the 75 patients, the degree of dementia deteriorated insiduously without any physical symptoms. The key person and/or caregiver was usually an elderly spouse, and the family noticed dementia only after cognitive impairment progressed with or without troublesome symptoms. Hallucination was a common troublesome symptom. Concerning consultation content, codes 1, 2, and 3 were common, while 13 cases had dissatisfaction with their medical treatment. Therefore, it was necessary to explain the significance of early diagnosis of dementia to families and their caregivers. There were also many families who felt strain and wondered about what hospital or department to take the patient to. In addition, it seemed that explanation on the clinical course and adverse drug reactions, advice for the correspondence with psychiatric symptoms and abnormal behaviour, and information services concerning utilization of social resources was not yet sufficient.
The vasorelaxant effects of the K(+)-channel openers, pinacidil and cromakalim, were compared with those of the Ca(2+)-channel blockers, verapamil and KB-2796 ...(1-bis(4-fluorophenyl)methyl-4-(2,3,4-trimethoxybenzyl)piperazine dihydrochloride), in canine isolated coronary, renal, basilar and mesenteric arteries precontracted with U46619, a thromboxane A2 mimetic. The relaxation induced by pinacidil and cromakalim was greater in coronary than in other arteries, the magnitude of relaxation being in the order of coronary > renal > basilar > mesenteric arteries. The relaxant responses to both drugs were inhibited by glibenclamide, a blocker of ATP-sensitive K+ channels. The relaxation induced by verapamil and KB-2796, in contrast, was greater in basilar than in other arteries, the magnitude of relaxation being in the order of basilar > coronary > renal and mesenteric arteries. In fura-2-loaded, U46619-stimulated arteries, pinacidil and cromakalim produced a greater reduction in intracellular Ca2+ concentration and muscle tension in coronary than in mesenteric arteries, while verapamil and KB-2796 reduced these values more potently in basilar than in mesenteric arteries. These results suggest that K(+)-channel openers exhibit a vasorelaxant selectivity for coronary arteries, whereas Ca(2+)-channel blockers exhibit such selectivity for cerebral arteries. The selective vasorelaxant action induced by these drugs appears to correspond, in part, to their effects on the concentration of intracellular Ca2+.
A sperm motility inhibitor from boar seminal plasma was purified. The purification procedure included dialysis against 0.1 M Tris-HCl containing 0.1 mM DTT and chromatographies on SP-Sephadex C-25 ...and Phenyl-Sepharose CL-4B. With this procedure, the seminal plasma motility inhibitor (SPMI) preparation was highly purified with a 18% recovery of inhibitory activity. The molecular weight of SPMI in native conditions has been estimated at 50,000 by molecular sieving, but 3 polypeptides with molecular weights of 14,000, 16,000 and 18,000 were observed following polyacrylamide gel electrophoresis in denaturing conditions. SPMI is a thermolabile basic protein that is stable between pH 6 and pH 11. The observations that SPMI effects on motility of demembranated spermatozoa are reversed by Mg.ATP and that SPMI inhibited bull dynein ATPase in a concentration-dependent manner suggest that this protein blocks the motility of demembranated spermatozoa by interfering with dynein arm function.
Three series of 22-residue peptides derived from the transmembrane M2 segment of the glycine receptor
α1-subunit (M2GlyR) have been designed, synthesized, and tested to determine the plasticity of a ...channel-forming sequence and to define whether channel pores with enhanced conductive properties could be created. Sixteen sequences were examined for aqueous solubility, solution-association tendency, secondary structure, and half-maximal concentration for supramolecular assembly, channel activity, and ion transport properties across epithelial monolayers. All peptides interact strongly with membranes: associating with, inserting across, and assembling to form homooligomeric bundles when in micromolar concentrations. Single and double amino acid replacements involving arginine and/or aromatic amino acids within the final five C-terminal residues of the peptide cause dramatic effects on the concentration dependence, yielding a range of
K
1/2 values from 36
±
5 to 390
±
220
μM for transport activity. New water/lipid interfacial boundaries were established for the transmembrane segment using charged or aromatic amino acids, thus limiting the peptides’ ability to move perpendicularly to the plane of the bilayer. Formation of discrete water/lipid interfacial boundaries appears to be necessary for efficient supramolecular assembly and high anion transport activity. A peptide sequence is identified that may show efficacy in channel replacement therapy for channelopathies such as cystic fibrosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To search for the intracellular signaling pathway critical for the pulmonary metastasis of osteosarcoma, we examined two osteosarcoma cell lines with different metastatic capability, Dunn and LM8. ...While parental Dunn is poorly metastatic to lung, LM8, derived from Dunn by in vivo selection through pulmonary metastasis, displays clear capability of pulmonary metastasis. We found that LM8 had higher levels of Akt phosphorylation and Ezrin expression than Dunn. In contrast, no clear difference was observed between Dunn and LM8 in other signaling mediators, including MAPK, SAPK and Stat3. In contrast to Dunn, LM8 secreted higher levels of matrix metalloproteinase-2 and -9, showed higher levels of invasiveness and cell motility, and displayed strong pulmonary metastasis. Inhibition of PI3K-Akt signaling in LM8 by a PI3K inhibitor, LY294002, or by a dominant negative form of Akt, resulted in suppression of MMP secretion, in vitro invasiveness, cell locomotion and in vivo pulmonary metastasis. In contrast, expression of an active form of Akt in Dunn substantially activated its MMP secretion, in vitro invasiveness, cell locomotion and in vivo pulmonary metastasis. Taken together, our results demonstrate, for the first time, an important role of Akt signaling in pulmonary metastasis of osteosarcoma.
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