Breast cancer in young women and prognosis: How important are proliferation markers?

AIM: Compared to middle-aged women, young women with breast cancer have a higher risk of systemic disease. We studied expression of proliferation markers in relation to age and subtype and their association with long-term prognosis. METHODS: Distant disease-free survival (DDFS) was studied in 504 women aged <40 years and 383 women aged ≥40 years from a population-based cohort. Information on patient characteristics, treatment and follow-up was collected from medical records. Tissue microarrays were produced for analysis of oestrogen receptor, progesterone receptor (PR), Her2, Ki-67 and cyclins. RESULTS: Young women with luminal tumours had significantly higher expression of Ki-67 and cyclins. Proliferation markers were prognostic only within this subtype. Ki-67 was a prognostic indicator only in young women with luminal PR+ tumours. The optimal cut-off for Ki-67 varied by age. High expression of cyclin E1 conferred a better DDFS in women aged <40 years with luminal PR- tumours (hazard ratio [HR] 0.47 [0.24-0.92]). Age <40 years was an independent risk factor of DDFS exclusively in women with luminal B PR+ tumours (HR 2.35 [1.22-4.50]). Young women with luminal B PR- tumours expressing low cyclin E1 had a six-fold risk of distant disease compared with luminal A (HR 6.21 [2.17-17.6]). CONCLUSIONS: The higher expression of proliferation markers in young women does not have a strong impact on prognosis. Ki-67 is only prognostic in the subgroup of young women with luminal PR+ tumours. The only cyclin adding prognostic value beyond subtype is cyclin E1. Age is an independent prognostic factor only in women with luminal B PR+ tumours.

Whi7 is an unstable cell-cycle repressor of the Start transcriptional program.

Start is the main decision point in eukaryotic cell cycle in which cells commit to a new round of cell division. It involves the irreversible activation of a transcriptional program by G1 CDK-cyclin complexes through the inactivation of Start transcriptional repressors, Whi5 in yeast or Rb in mammals. Here we provide novel keys of how Whi7, a protein related at sequence level to Whi5, represses Start. Whi7 is an unstable protein, degraded by the SCFGrr1 ubiquitin-ligase, whose stability is cell cycle regulated by CDK1 phosphorylation. Importantly, Whi7 associates to G1/S gene promoters in late G1 acting as a repressor of SBF-dependent transcription. Our results demonstrate that Whi7 is a genuine paralog of Whi5. In fact, both proteins collaborate in Start repression bringing to light that yeast cells, as occurs in mammalian cells, rely on the combined action of multiple transcriptional repressors to block Start transition.The commitment of cells to a new cycle of division involves inactivation of the Start transcriptional repressor Whi5. Here the authors show that the sequence related protein Whi7 associates to G1/S gene promoters in late G1 and collaborates with Whi5 in Start repression.

Expresión de las proteínas FGFR3, PI3K, AKT, p21Waf1/Cip1 y ciclinas D1 y D3 en pacientes con tumores de vejiga T1: implicaciones clínicas y significado pronóstico / Expression of proteins FGFR3, PI3K, AKT, p21Waf1/Cip1 and cyclins D1 and D3 in patients with T1 bladder tumours: clinical implications and prognostic significance

Objetivo: Determinar la expresión proteica diferencial de los biomarcadores FGFR3, PI3K (subunidades PI3Kp110α, PI3KClassIII, PI3Kp85), AKT, p21Waf1/Cip1 y las ciclinas D1 y D3 en el cáncer de vejiga T1 versus tejido sano, así como estudiar su posible papel como marcadores de recidiva precoz. Material y método: Se trata de un estudio prospectivo en el que se utilizaron un total de 67 muestras de tejido (55 casos de tumores de vejiga T1 sometidos a resección transuretral y 12 casos de mucosa sana adyacente). Los niveles de expresión de las proteínas se evaluaron mediante Western blot, y las medias y los porcentajes fueron comparados utilizando el test «t» de Student y la prueba Chi cuadrado. El análisis de supervivencia se realizó mediante el método Kaplan-Meier y el test Log-rank. Resultados: Se detectó una mayor expresión proteica de FGFR3, PI3Kp110α, PI3KClassIII, ciclinas D1 y D3 y p21Waf1/Cip1 en tejido tumoral versus mucosa sana. Sin embargo, estas diferencias no fueron significativas para PI3Kp85 y AKT. Se observaron correlaciones estadísticamente significativas de PI3Kp110α, PI3KClassIII, PI3Kp85 y AKT con la recidiva temprana (p = 0,003, p = 0,045, p = 0,050 y p = 0,028 respectivamente), de ciclina D3 (p=0,001) con el tipo tumoral (primario versus recidivante), de FGFR3 (p = 0,035) con el tamaño tumoral y de ciclina D1 (p = 0,039) con la multifocalidad. El análisis de supervivencia seleccionó a FGFR3 (p = 0,024), PI3Kp110alfa (p = 0,014), PI3KClassIII (p = 0,042) y AKT (p= 0,008) como marcadores de supervivencia libre de recidiva precoz. Conclusiones: Existe un incremento de los niveles de expresión proteica en el tejido tumoral vesical, asimismo, la sobreexpresión de FGFR3, PI3Kp110α, PI3KClassIII y AKT se asocia con una mayor supervivencia libre de recidiva precoz en pacientes con tumores de vejiga T1

Objective: To determine the differential protein expression of biomarkers FGFR3, PI3K (subunits PI3Kp110α, PI3KClassIII, PI3Kp85), AKT, p21Waf1/Cip1 and cyclins D1 and D3 in T1 bladder cancer versus healthy tissue and to study their potential role as early recurrence markers. Material and method: This is a prospective study that employed a total of 67 tissue samples (55 cases of T1 bladder tumours that underwent transurethral resection and 12 cases of adjacent healthy mucosa). The protein expression levels were assessed using Western blot, and the means and percentages were compared using Student's t-test and the chi-squared test. The survival analysis was conducted using the Kaplan-Meier method and the log-rank test. Results: Greater protein expression was detected for FGFR3, PI3Kp110α, PI3KClassIII, cyclins D1 and D3 and p21Waf1/Cip1 in the tumour tissue than in the healthy mucosa. However, these differences were not significant for PI3Kp85 and AKT. We observed statistically significant correlations between early recurrence and PI3Kp110α, PI3KClassIII, PI3Kp85 and AKT (P = .003, P = .045, P = .050 and P = .028, respectively), between the tumour type (primary vs. recurrence) and cyclin D3 (P=.001), between the tumour size and FGFR3 (P = .035) and between multifocality and cyclin D1 (P = .039). The survival analysis selected FGFR3 (P = .024), PI3Kp110α (P = .014), PI3KClassIII (P = .042) and AKT (P = .008) as markers of early-recurrence-free survival. Conclusions:. There is an increase in protein expression levels in bladder tumour tissue. The overexpression of FGFR3, PI3Kp110α, PI3KClassIII and AKT is associated with increased early-recurrence-free survival for patients with T1 bladder tumours

Re-expression of cell cycle markers in aged neurons and muscles: Whether cells should divide or die?

Emerging evidence revealed that abrogated cell cycle entry into highly differentiated mature neurons and muscles is having detrimental consequences in response to cell cycle checkpoints disruption, altered signaling cascades, pathophysiological and external stimuli, for instance, Aß, Parkin, p-tau, α-synuclein, impairment in TRK, Akt/GSK3ß, MAPK/Hsp90, and oxidative stress. These factors, reinitiate undesired cell division by triggering new DNA synthesis, replication, and thus exquisitely forced mature cell to enter into a disturbed and vulnerable state that often leads to death as reported in many neuro- and myodegenerative disorders. A pertinent question arises how to reverse this unwanted pathophysiological phenomenon is attributed to the usage of cell cycle inhibitors to prevent the degradation of crucial cell cycle arresting proteins, cyclin inhibitors, chaperones and E3 ligases. Herein, we identified the major culprits behind the forceful cell cycle re-entry, elucidated the cyclin re-expression based on disturbed signaling mechanisms in neuromuscular degeneration together with plausible therapeutic strategies.

miRNA-202 in bone marrow stromal cells affects the growth and adhesion of multiple myeloma cells by regulating B cell-activating factor.

Bone marrow stromal cells (BMSCs) up-regulate B cell-activating factor (BAFF) in multiple myeloma. Increasing experimental evidence has shown that microRNAs play a causal role in hematology tumorigenesis. In this study, we characterized the role of miR-202 in regulating the expression of BAFF in BMSCs. It was found that expressions of BAFF mRNA and protein were increased in BMSCs treated with miR-202 inhibitor. The growth rate of miR-202 mimics transfection cells was significantly lower than that of non-transfected cells. The expression of Bcl-2 protein was down-regulated, and Bax protein was up-regulated after miR-202 mimics transfection. Over-expression of miR-202 in BMSCs rendered MM cells more sensitive to bortezomib. More significantly, the regulatory effect of miR-202 could inhibit the activation of NF-κB pathway in BMSCs. These results suggest that miR-202 functions as a modulator that can negatively regulate BAFF by inhibiting MM cell survival, growth, and adhesion in the bone marrow microenvironment.

Inhibitory Effects of Enterolactone on Growth and Metastasis in Human Breast Cancer.

A lignan-rich diet is associated with a lower risk of human breast cancer. Enterolactone, an active polyphenol metabolites of lignan, was reported to have an antitumor effect. We investigated the mechanism for the effect of enterolactone against human breast cancer. Cellular changes, and associated genes induced by enterolactone, were investigated in MDA-MB-231 cells. Enterolactone showed an antiproliferative effect, and its IC50 was 261.9 ± 10.5 µM for a treatment period of 48 hr. The mRNA levels of the genes related to cell proliferation, Ki67, PCNA, and FoxM1, were reduced. Enterolactone induced accumulation of cells in the S phase, and a lower expression of Cyclin E1, Cyclin A2, Cyclin B1, and Cyclin B2 genes. There were almost no changes in the transcription levels of the genes that participate in G0/G1 phase regulation, CDK4, CDK6, and Cyclin D1. Furthermore, enterolactone interfered with the cytoskeleton by downregulating phosphorylation of the FAK/paxillin pathway, inhibiting migration and invasion of cells. The results suggest that enterolactone exerts an antitumor effect by regulating the expression of genes associated with cell proliferation and the cell cycle and by blocking the FAK/paxillin signaling pathway. These findings provide new insights into the molecular mechanisms behind the antitumor effect of enterolactone.

Pursuing the impossible: an interview with Tim Hunt.

Tim Hunt took an undergraduate degree in Natural Sciences at Cambridge in 1964, and his PhD and subsequent work focussed on the control of protein synthesis until 1982, when his adventitious discovery of the central cell cycle regulator cyclin, while he was teaching at the Marine Biological Laboratory in Woods Hole, redirected him to the study of cell cycle regulation. From 1990 to his retirement Tim worked in the Clare Hall Laboratories of Cancer Research UK. He shared the Nobel Prize in Physiology and Medicine with Lee Hartwell and Paul Nurse in 2001, and talked to us about the series of coincidences that led him to the prizewinning discovery.

Expression of AKR1C3 and CNN3 as markers for detection of lymph node metastases in colorectal cancer.

The aim of the study was to identify a set of discriminating genes that could be used for the prediction of Lymph node (LN) metastasis in human colorectal cancer (CRC), and for this, we compared the whole genome profiles of two CRC cell lines (the primary cell line SW480 and its LN metastatic variant, SW620) and identified eight genes [S100 calcium-binding protein P; aldo-keto reductase family 1(AKR1), member B1 (aldose reductase; AKR1B1); AKR1, member C3 (AKR1C3); calponin 3, acidic; metastasis associated in colon cancer 1; hemoglobin, epsilon 1; trefoil factor 3; and FGGY carbohydrate kinase domain containing]. These genes were examined by quantitative RT-PCR in tissues and LNs in 14 CRC patients and 11 control patients. The level of AKR1C3 mRNA expression was significantly different between the Dukes' stage A, B, and C groups and the control group (p < 0.05, p < 0.001, and p < 0.001) and was also significantly different between Dukes' stage C and A or B groups (p < 0.05 and p < 0.001, respectively). The expression of CNN3 was significantly different between the Dukes' stage C and B or control groups (p < 0.001 and p < 0.01, respectively). There were significant correlations between the expression levels of AKR1C3 and CNN3. AKR1C3 and CNN3 expressions are more accurate and suitable markers for the diagnosis of LN metastasis than the other six genes examined in this study.

Valor pronóstico de los receptores hormonales, receptor del factor de crecimiento epidérmico humano, ciclinas D1 y D2, B-Cell Lymphoma2 y ciclooxigenasa-2 en pacientes jóvenes con cáncer de mama / Prognostic value of hormone receptors, human epidermal growth factor receptor, cyclins D1 and D2, B-cell lymphoma 2 and cyclooxygenase-2 in young patients with breast cancer

Objetivo: Valor pronóstico de receptores hormonales (RRHH), expresión de HER-2, ciclinas D1 y D2, bcl-2 y ciclooxigenasa-2 (COX-2) en pacientes de 35 años o menores con cáncer de mama. Sujetos y método: En una serie de 71 pacientes jóvenes, cuya evolución se conocía, analizamos por segunda vez las piezas tumorales mediante inmunohistoquímica y tissue arrays. Evaluamos la influencia pronóstica de estos factores con el test de la chi al cuadrado y el método de Kaplan-Meier. Resultados: El 67% de las pacientes mostraban RRHH positivos y el 48,6% sobreexpresaba el HER- 2. Fueron ciclinas D1 y D2 positivos el 59,1% y 59,7%, respectivamente. El bcl-2 en el 62,5% de los casos, y la COX-2 en el 63,4% de los tumores. La positividad de RRHH y de COX-2 se relacionó significativamente con un mayor riesgo de recidiva local (OR = 4,6, p = 0,03 para RRHH y OR = 3,7, p = 0,02 para COX-2). Conclusiones: La sobreexpresión de RRHH y COX-2 desempeña un papel pronóstico en la progresión del cáncer de mama en mujeres muy jóvenes. La expresión de ciclinas D1 y D2, y bcl-2 no influyó en su evolución(AU)

Objetive: To investigate the value of hormone receptor (HR) status, HER-2, cyclins D1 and D2, bcl-2 and cyclooxygenase-2 (COX-2) in predicting the outcome of very young breast cancer patients (below 35 years). Subjects and method: In this study HR, HER-2, cyclins D1 and D2, bcl-2 and COX-2 were determined for a second time by immunohistochemistry and tissue arrays in a cohort of 71 patients aged less than 35 years with known outcome. The prognostic influence of these factors was evaluated by the chi-square test and Kaplan Meier method. Results: Expression of HR was detected in 67% of the patients, HER-2 in 48.6%, cyclins D1 and D2 in 59.1% and 59.7%, respectively, bcl-2 in 62.5% and COX-2 in 63.4% of breast tumors. HR and COX- 2 overexpression were significantly correlated with a major risk of local relapse (OR: 4.6, P=.03 for HR and OR: 3.7, P=.02 for COX-2). Conclusions: Increased expression of HR and COX-2 may play a role in the progression of primary breast carcinoma in very young patients. Overexpression of cyclins D1 and D2 and bcl-2 had no prognostic value(AU)

Gallic acid induces G2/M phase arrest of breast cancer cell MCF-7 through stabilization of p27(Kip1) attributed to disruption of p27(Kip1)/Skp2 complex.

Gallic acid (GA), 3,4,5-trihydroxybenzoic acid, is a natural polyphenolic acid and widely found in gallnuts, tea leaves and various fruits. Previous studies have shown that GA possesses anti-inflammatory, antiallergic and anticarcinogenic activity. In the present study, we aim to investigate the antitumor effects of GA on breast cancer cell. Our results revealed that GA treatment significantly reduced the cell growth of human breast cancer cell MCF-7 in a dose-dependent manner. Further flow cytometric analysis showed that GA induced significant G2/M phase arrest but slightly affected the population of sub-G1MCF-7 cells. Therefore, levels of cyclins, cyclin-dependent kinases (CDKs), and their regulatory proteins involved in S-G2/M transition were investigated. Our findings revealed that levels of cyclin A, CDK2, cyclin B1 and cdc2/CDK1 were diminished; in contrast, levels of the negative regulators p27(Kip1) and p21(Cip1) were increased by GA treatment. Additionally, Skp2, a specific ubiquitin E3 ligase for polyubiquitination of p27(Kip1) was reduced by GA treatment. Further investigation showed that GA attenuated Skp2-p27(Kip1) association and diminished polyubiquitination of p27(Kip1) in MCF-7 cells. Moreover, knockdown of p27(Kip1) but not p21(Cip1) significantly alleviated GA-induced accumulation of G2/M phase. These findings indicate that GA may upregulate p27(Kip1) level via disruption of p27(Kip1)/Skp2 association and the consequent degradation of p27(Kip1) by proteosome, leading to G2/M phase arrest of MCF-7 cell. It is suggested that GA should be beneficial to treatment of breast cancer and p27(Kip1)-deficient carcinomas.

Biomarkers in bladder cancer.

Cancer biomarkers provide an opportunity to diagnose tumours earlier and with greater accuracy. They can also identify those patients most at risk of disease recurrence and predict which tumours will respond to different therapeutic approaches. Such biomarkers will be especially useful in the diagnosis and management of bladder cancer. At present, bladder tumours are diagnosed and followed-up using a combination of cystoscopic examination, cytology and histology. These are not only expensive, but also highly subjective investigations and reveal little about the underlying molecular characteristics of the tumour. In recent years numerous diagnostic and prognostic biomarkers of bladder cancer have been identified. Two separate approaches to biomarker discovery have been employed. The first is hypothesis-driven and focuses upon proteins involved in molecular pathways known to be implicated in tumorigenesis. An alternative approach has been to study the global expression of genes (so-called 'genomics') looking for characteristic signatures associated with disease outcomes. In this review we summarize the current state of biomarker development in this field, and examine why so few have made the successful transition into the clinic. Finally, we introduce a novel approach to biomarker development utilizing components of the DNA replication licensing machinery.

Clinicopathological significance of cell cycle regulatory factors and differentiation-related factors in pancreatic neoplasms.

OBJECTIVES: The aim of the present study was to compare the expression levels of the cyclins and the differentiation-related factors in pancreatic neoplasms. METHODS: The expression levels of cyclins A and B1, E1A-like inhibitor of differentiation 1 (EID-1), p300, 3'-5'-cyclic sdenosine monophosphate response element binding protein (CREB) binding protein (CBP), and acetylated histone H3 (AcH3) in ordinary ductal carcinoma (ODC) and intraductal papillary mucinous neoplasms (IPMNs) of the pancreas were investigated. RESULTS: More cells positive for cyclin A and EID-1 were present in the ODC than in the IPMNs. Cells positive for both cyclins and EID-1 were observed more frequently in invasive carcinoma derived from the IPMN than from the IP mucinous carcinoma. Multivariate regression analysis revealed that EID-1 and cyclin A overexpressions were independent factors associated with poor prognosis. Overall survival was significantly lower in ODC patients with overexpressions of cyclin A, EID-1, and AcH3 than in those without such overexpressions. There were significant differences in the survival curves between patients with ODC and invasive carcinoma derived from IPMN, regarding high frequency for cyclin A or B1. CONCLUSIONS: These results indicated that the expressions of cyclins A and B1, EID-1, and AcH3 may be correlated with a malignant potential in IPMNs. Invasive carcinoma derived from IPMN may be slow growing as compared with ODC.

Altered expression of key cell cycle regulators in renal cell carcinoma associated with Xp11.2 translocation.

Renal cell carcinoma (RCC) is a rare tumor in the pediatric population. Recently, a phenotypically and genetically distinct kidney carcinoma, mainly prevalent in children and associated with an Xp11.2 translocation or TFE3 gene fusion, has been described. It has been advanced that in this subtype of RCC, there is an accumulation of cyclin D1, cyclin D3, and p21 ((wafl/cip1)). The aim of the present study was to figure out in two pediatric RCC recently diagnosed in our department (one clear cell-type RCC and one TFE3-positive RCC) whether those features are indeed specific of the latter tumor or occur in pediatric RCC irrespective of the tumor type. The following immunostains were performed in both cases: Ki67, p16(ink4a), p21 ((wafl/cip1)), p27(kip1), p53, p63, mdm2, cyclin D1, cyclin D3, TFE3, CD10, vimentin, E-cadherin, and RCC-antigen. We observed in the TFE3-positive carcinoma an intense immunoreaction for p21 ((wafl/cip1)), cyclin D1, and cyclin D3, without expression for p53, p16, p27(kip1), and mdm2, whereas the immunoexpression profile observed in the classic RCC was similar to that of clear cell, adult-type RCC. Our study confirms that TFE3-positive RCC exhibits a deregulation of the cell cycle apparently unrelated to the young age of the patients.

Clinicopathologic features of CDK6 translocation-associated B-cell lymphoproliferative disorders.

Cyclin-dependent protein kinase 6 (CDK6), in cooperation with cyclin Ds, drives cell cycle progression from G1 to S phase through phosphorylation and subsequent inactivation of retinoblastoma 1 protein. Alteration of this pathway results in both nonhematologic and hematologic malignancies, which include a small subset of B-cell lymphoproliferative disorders (BLPDs). We identified 5 cases of BLPD that carried CDK6 chromosomal translocations and characterized their clinical, pathologic, immunophenotypic, and genetic features. Common clinical characteristics included marked neoplastic lymphocytosis, systemic lymphadenopathy, splenomegaly, and bone marrow involvement. Three patients were diagnosed with low-grade B-cell lymphoma and had an indolent clinical course, and 2 patients (one who transformed to large B-cell lymphoma, and the other who was initially diagnosed with a high-grade B-cell lymphoma) had an aggressive clinical course. Immunophenotypically, the neoplastic B cells expressed CD5, CDK6, and cytoplasmic retinoblastoma 1 protein in all cases, expressed phospho-RB, p27kip1, and cyclin D2 in most cases, and uniformly lacked expression of all other cyclins. In 4 cases, the CDK6 translocation partner was kappa immunoglobulin light-chain gene; and in the fifth case, the CDK6 translocation partner was unknown. These distinct clinicopathologic and cytogenetic features distinguish the CDK6 translocation-associated BLPDs (CDK6-BLPDs) from other mature B-cell lymphomas.

Recombinant human arginase inhibits proliferation of human hepatocellular carcinoma by inducing cell cycle arrest.

Human hepatocellular carcinoma (HCC) has an elevated requirement for arginine in vitro, and pegylated recombinant human arginase I (rhArg-PEG), an arginine-depleting enzyme, can inhibit the growth of arginine-dependent tumors. While supplementation of the culture medium with ornithine failed to rescue Hep3B cells from growth inhibition induced by rhArg-PEG, citrulline successfully restored cell growth. The data support the roles previously proposed for ornithine transcarbamylase (OTC) in the arginine auxotrophy and rhArg-PEG sensitivity of HCC cells. Expression profiling of argininosuccinate synthetase (ASS), argininosuccinate lyase (ASL) and OTC in 40 HCC tumor biopsy specimens predicted that 16 of the patients would be rhArg-sensitive, compared with 5 who would be sensitive to arginine deiminase (ADI), another arginine-depleting enzyme with anti-tumor activity. Furthermore, rhArg-PEG-mediated deprivation of arginine from the culture medium of different HCC cell lines produced cell cycle arrests at the G(2)/M or S phase, possibly mediated by transcriptional modulation of cyclins and/or cyclin dependent kinases (CDKs). Based on these results, together with further validation of the in vivo efficacy of rhArg-PEG against HCC, we propose that the application of rhArg-PEG alone or in combination with existing chemotherapeutic drugs may represent a specific and effective therapeutic strategy against HCC.

Distinct mechanisms act in concert to mediate cell cycle arrest.

In response to DNA damage, cells arrest at specific stages in the cell cycle. This arrest must fulfill at least 3 requirements: it must be activated promptly; it must be sustained as long as damage is present to prevent loss of genomic information; and after the arrest, cells must re-enter into the appropriate cell cycle phase to ensure proper ploidy. Multiple molecular mechanisms capable of arresting the cell cycle have been identified in mammalian cells; however, it is unknown whether each mechanism meets all 3 requirements or whether they act together to confer specific functions to the arrest. To address this question, we integrated mathematical models describing the cell cycle and the DNA damage signaling networks and tested the contributions of each mechanism to cell cycle arrest and re-entry. Predictions from this model were then tested with quantitative experiments to identify the combined action of arrest mechanisms in irradiated cells. We find that different arrest mechanisms serve indispensable roles in the proper cellular response to DNA damage over time: p53-independent cyclin inactivation confers immediate arrest, whereas p53-dependent cyclin downregulation allows this arrest to be sustained. Additionally, p21-mediated inhibition of cyclin-dependent kinase activity is indispensable for preventing improper cell cycle re-entry and endoreduplication. This work shows that in a complex signaling network, seemingly redundant mechanisms, acting in a concerted fashion, can achieve a specific cellular outcome.

Factores moleculares pronósticos relacionados con el control del ciclo celular en el cáncer de mama. Situación actual / Molecular prognostic factors related to cell cycle in breast cancer. Current situation

El cáncer de mama es una de las enfermedades malignas más frecuentes en las mujeres. Su incidencia se ha ido incrementando cada año hasta considerarse un problema sanitario de características epidémicas. Alrededor de un 15% de las mujeres desarrolla cáncer de mama a lo largo de su vida. En los últimos años se ha realizado una gran cantidad de trabajos sobre los factores de riesgo y pronósticos de esta enfermedad. En esta revisión de la bibliografía científica, se presenta el estado actual de los factores pronósticos relacionados con la regulación del ciclo celular en el cáncer de mama (AU)

Breast cancer is one of the most common malignancies among women. The incidence of this disease has been increasing yearly and it could now be considered an epidemic disease. Approximately 15% of women will develop this kind cancer during their lifetime. In the last few years, multiple studies have been carried out on the risk and prognostic factors of breast cancer. We provide a review of the scientific literature on the current situation of molecular prognostic factors for breast cancer related to cell cycle control (AU)

[Proliferation markers used in histological studies].

The present paper reviews the current approaches used to study cell proliferative activity. In the last years, a number of proteins involved in cell cycle control were discovered, that may serve as selective markers of proliferating cells. This work gives the characteristics of immunocytochemical methods demonstrating 5-bromodeoxyuridine, PCNA, Ki-67, FEN-1, phosphorylated histone H3 and cyclins. The data on the role of these proteins in cell cycle control are presented.

[The initial mechanism's investigation of pilose antler polypeptides resisting replicative senescence of rat chondrocyte].

OBJECTIVE: To investigate the mechanism of pilose antler polypeptides (PAP) resisting replicative senescence of rat chondrocyte serially subcultivated in vitro by means of PAP interfering and controlled experiment. METHODS: The successive tert-generation (2nd passage, 3rd passage, 4th passage) chondrocytes and the 4th passage cells intervented by PAP were studied for senenscence mechanism. In this course, immunocytochemistry was applied for pl6, pRb, E2F, CyclinD, CDK4 and TRAP-ELISA (telomerase repeat amplification protocol assay-enzyme linked immunosorbent assay) was applied for telomerase activation to observe targets' changing regarding to senescence and the function of PAP. RESULTS: Along with cell's replicative senescence, pl6, pRb and Cyclin D express significantly rised (P < 0.01), while E2F, CDK4 and telomerase express significantly lowerd (P < 0.01). Meanwhile, in PAP interfered group compared with which in 4th passage group, pl6, pRb and Cyclin D express significantly lowerd (P < 0.01l), while E2F, CDK4 and telomerase express significantly rised (P < 0.01). CONCLUSION: PAP has function that it reversingly affect the express of factors which controlling cell life cycle and cell growth to postpone chondrocyte senenscence.

[The significance of immunohistochemistry in the investigation of liver neoplasms: differential diagnosis, prognostic markers].

The immunohistochemical investigation used 55 primary hepatic tumors (hepatocellular carcinoma (HCC)--32, cholangiocellular carcinoma (CCC)--23). Wide panels of such antibodies as hepatocytic marker (Hep Par--1) CK-8, CK-19, polyclonal CEA, CD10, alpha-fetoprotein, TTF-1 as well as proliferative features of HCC (Ki-67) including regulators of stage-to-stage transition through mitoses of tumor cells (cyclin-D1 and A, genes p53 and RB), unrestricted tumor cell mitosis (telomerases), and intercellular adhesion marker (beta-catenin) were employed for differential diagnosis of neoplasia. The most efficient marker HCC was Hep Par--l (sensitivity--100%, specificity--92%) while the sensitivity of CCC (CK-19) was 83% and specificity--78%. Of particular importance for differentiation between HCC and CCC were the nature of microcirculatory flow identifiable with the aid of CD31 and presence of pseudocapsule in HCC detected by means of calponin. CEA and CD10 played a part too while the remaining markers were either expressed very seldom (alpha-fetoprotein) or absent (TTF-1). Most nuclear antigens (Ki-67, cyclin-A, p53 and RB) were intensely expressed in poorly-differentiated HCC cells. Cyclin-D1 and mutated suppressor-gene p53 expression involved lowered overall and relapse-free survival.