RESUMEN
BACKGROUND: The oncoprotein p53 protein induces cell growth arrest (apoptosis) in response to endoâ or exogenous stimuli. Mutation of TP53 (gene encoding the p53 protein) is common in human malignancies and alters the conformation of p53. The result is a more stable protein which accumulates in nuclei of tumor cells with loss of function. Mutant p53 is stabilized, and it is possible to detect this form very clearly by immunohistochemistry (IHC). Expression of the MDM2 protein is used as a potential marker of p53 function. P53 levels in normal cells are highly determined by the MDM2 protein (murine double minuteâ2) -â mediated degradation of p53. MDM2 overexpression represents at least one mechanism by which p53 function can be abrogated during tumorigenesis. MATERIAL AND METHODS: Lung carcinoma samples were obtained from patients, who underwent radical resection (lobectomy or pulmonectomy and lymphadectomy). Pathological dia-gnosis was based on the WHO criteria. In our study, we investigated the expression of p53 and MDM2 protein that might improve IHC as a marker for p53 status. Proteins were IHC detected in 136 samples of primary lung carcinoma. Immunostaining results of p53 positive samples were compared to IHC expression of MDM2 positive and MDM2 negative samples. RESULTS: Strong brown nuclear staining was visible in p53 and MDM2 positive cells. The most p53 positive cases were samples of squamocellular carcinoma (55%), then samples of large cell carcinoma (53%) and 26% adenocarcinoma samples showed the p53 immunoreactivity. No one sample of different types was p53 positive. When we compared the p53 expression and grade of tumor, we found that the p53 expression increased with the grade of tumor. For statistical evaluation, the chiâsquare test was used. The relationship between p53 expression and type of tumor, also the p53 expression and grade of tumor was statistically significant (p = 0.000425; p = 0.00157). Regarding p53 and MDM2 expression, only nine samples (7%) were simultaneously p53 and MDM2 positive. In 46 (34%) cases, elevation of p53 was combined with MDM2 negative expression. Other tumor samples were either negative for both proteins (71/â52%), or p53 negative and MDM2 positive in 10 (7%) tumor samples. CONCLUSION: Absence of p53 staining in most studies indicates absence of p53 mutation, and on the contrary, positive expression of p53 is a sign of p53 mutations with loss of function. In our study, 34% of cases with extensively high level of p53 without increased level of MDM2 were identified. We suppose that these are tumors with inactivating mutations that stabilize p53. On the other hand, tumors with high level of stabilized wildtype p53 protein and simultaneously with increased MDM2 staining (9 samples/7%) represent group with functional p53. In this group of patients, we could expect better prognosis with regard to function of p53 protein.
Asunto(s)
Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas c-mdm2/análisis , Proteínas Proto-Oncogénicas/análisis , Proteína p53 Supresora de Tumor/análisis , Genes p53 , Humanos , Inmunohistoquímica , Proteínas de Neoplasias/análisisRESUMEN
BACKGROUND: Proteins XRCC1 and ERCC1 are involved in DNA repair. XRCC1 plays a role in DNA base excision repair and ERCC1 in nucleotide excision repair pathway. Higher expression profile of both proteins in cancer cells may contribute to development of drug resistance. ERCC1 is involved in removal of platinum adducts and might be a potential predictive and prognostic marker in NSCLC (non-small-cell lung cancer) treated with a cisplatin-based regimen. The purpose of study was determination of XRCC1 and ERCC1 levels and their correlation with basic clini-copathological parameters in NSCLC. PATIENTS AND METHODS: In this study, 107 tumor samples diagnosed as NSCLC were immunohistochemically examined for expression of XRCC1 and ERCC1 proteins. Our results were compared to basic clinicopathological parameters: type of tumor, tumor grade and stage of disease. For statistical analysis, the chi-square test was used. RESULTS: In squamous cell carcinoma and large cell carcinoma samples, the XRCC1 protein level was twofold higher (60% of positive samples) than in adenocarcinoma samples (35.5% of positive samples). We have found statistical correlation between XRCC1 protein expression and type of tumor (p = 0.0306). On the other hand, the statistical importance between the protein level versus grade and stage was not found. In the case of the ERCC1 protein, we observed the highest protein level in adenocarcinoma (64.5%) and squamous cell carcinoma (62.5%) samples. Next, we determined a significant difference in content of XRCC1 versus ERCC1 (35.5% vs 64.5%) in adenocarcinoma samples. Statistical chi-square test did not reveal any correlation between ERCC1 status and clinicopathological parameters. CONCLUSION: According to our results, XRCC1 represents an important mechanism of DNA repair in squamous cell and large cell carcinomas. Besides that, expression of XRCC1 was in correlation with type of tumor. In patients with adenocarcinoma and squamous cell carcinoma, we could assume increased resistance to platinum-based therapy because of high expectation of ERCC1 protein expression. However, its levels did not correlate with monitored clinicopathological parameters. The ERCC1 protein will be possibly an independent prognostic factor in NSCLC. To prove a true survival benefit of patients with expression of ERCC1, prospective validation of ERCC1 before clinical implication is needed in the future.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Reparación del ADN , Proteínas de Unión al ADN/metabolismo , Endonucleasas/metabolismo , Neoplasias Pulmonares/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Humanos , Neoplasias Pulmonares/genética , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos XRESUMEN
OBJECTIVE: Localization of monoamine oxidases (MAO) in rat female gonads during preimplantation period of pregnancy was determined. MATERIAL AND METHODS: Pregnant females were killed on their first, third, and fifth days of pregnancy and animals were transcardially perfused with PBS and fixative solutions. Ovaries, oviducts and uteri were immediately removed and they served for the determination of MAO localization employing the method of enzymatic histochemistry. RESULTS: MAO-A activity in ovary was visible in corpora lutea and in interstitial gland cells while MAO-B was detected predominantly in blood vessels. Both MAO enzymes were seen in the smooth muscle fibers of the ovarian hilum. The presence of MAO enzymes was however not detected in follicles at any stage of their development. In oviduct and uterus, both MAO enzymes were visible in similar places, namely in smooth muscle fibers, mast cells and blood vessels, with no MAO presence seen in the epithelium. CONCLUSIONS: Potential physiological importance of MAO localization in different cells of female reproductive organs during early period of pregnancy is proposed (Fig. 6, Ref. 29).
Asunto(s)
Blastocisto , Genitales Femeninos/enzimología , Monoaminooxidasa/metabolismo , Animales , Trompas Uterinas/enzimología , Femenino , Ovario/enzimología , Embarazo , Ratas , Ratas Wistar , Útero/enzimologíaRESUMEN
OBJECTIVE: We have evaluated the impact of chronic administration of clorgyline, a potent monoamine oxidase A inhibitor and a former antidepressant, on the preimplantation embryo development in Wistar rats. MATERIAL AND METHODS: Females were injected intraperitoneally daily for 30 days with saline (control animals, C), or with a low dose of clorgyline (0.1 mg/kg/day, LDC) or with a high dose of clorgyline (1 mg/kg/day, HDC). Embryos were isolated on day 5 of pregnancy and their urine was collected. RESULTS: The number of embryos per female did not differ between experimental groups and control, but we have recorded a decreased number of embryos in HDC group compared to LDC (p < 0.05). We have found that LDC significantly reduced the presence of healthy embryos and increased the presence of the degenerated embryos (p < 0.001). The administration of the LDC resulted in the lowest cell number in blastocysts (p < 0.01). Concerning monoamines in urine, we have observed significantly increased serotonin levels in HDC group compared to control (p < 0.05) and LDC animals (p < 0.01). Norepinephrine levels in both experimental groups were significantly elevated compared to controls, too (p < 0.001 LDC vs C; p < 0.01 HDC vs C). CONCLUSIONS: We assume that the impaired embryo development recorded in the LDC group after clorgyline administration was a consequence of the higher levels of the norepinephrine. We speculate that lesser negative effect of HDC compared to LDC on the preimplantation embryo development could be the consequence of the lesser norepinephrine levels and/or elevated serotonin levels (Tab. 2, Fig. 2, Ref. 37). Full Text in free PDF www.bmj.sk.
Asunto(s)
Desarrollo Embrionario/efectos de los fármacos , Norepinefrina/sangre , Serotonina/sangre , Animales , Clorgilina/farmacología , Femenino , Inhibidores de la Monoaminooxidasa/farmacología , Embarazo , Ratas , Ratas WistarRESUMEN
OBJECTIVES: The aim of our work was to determine the expression of Pi class glutathione S-transferase (GSTP1) in 43 samples of invasive breast carcinoma and compare results versus normal breast cells. BACKGROUND: Breast cancer is the commonest cancer in women. Despite advances in early detection and more efficacious adjuvant chemotherapy, a part of patients with early-stage have reccurent disease. In these cases the development of resistance to therapy is observed. The glutathione S-transferases (GSTs) are potentially involved in tumour chemoresistance. METHODS: Enzyme immunohistochemical method was chosen for the detection of GSTP1 and its expression was compared in breast cancer cells versus normal breast cells. RESULTS: We have found that majority (63%) of breast carcinomas shows GSTP1 positivity (nuclear and cytoplasmic immunoreactivity). It is expected that GSTP1 positive tumours would show a poorer prognosis than GSTP1 negative ones. CONCLUSION: Immunohistochemistry is a useful method for investigating the expression and cellular localization of GSTP1 within tumours. It may be applied to a routine clinical test and it can serve as a marker for resistance to chemotherapy (Tab. 1, Fig. 4, Ref. 20). Full Text in free PDF www.bmj.sk.
Asunto(s)
Neoplasias de la Mama/química , Carcinoma Ductal de Mama/química , Carcinoma Lobular/química , Gutatión-S-Transferasa pi/metabolismo , Femenino , Humanos , InmunohistoquímicaRESUMEN
The aim of our work was to determine the expression of glycoprotein 96 (gp96; glucose-regulated protein 94 - GRP94) in 69 samples of breast carcinoma. Enzyme immunohistochemical method was chosen for the detection of gp96 protein and its expression was compared in breast cancer cells versus normal breast cells. We found higher expression of gp96 protein in breast carcinoma cells and low or no expression in normal breast cells. Furthermore, we demonstrate first time, that ductal invasive breast carcinomas showed higher expression of gp96 than lobular invasive breast carcinomas.
Asunto(s)
Antígenos de Neoplasias/metabolismo , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Biomarcadores de Tumor , Mama/metabolismo , Femenino , Humanos , Técnicas para InmunoenzimasRESUMEN
A large number of renal cancer patients show poor or partial response to chemotherapy and the precise mechanism has not been understood yet. MDR is the principal mechanism by which many cancers develop resistance to chemotherapeutic drugs and is associated with the elevated expression of MDR proteins. These are divided into two groups: ABC transporters and non-ABC transporters. The aim of our study was to determine the expression of MDR1/Pgp, MRP1 and LRP in 47 samples of renal cell carcinomas using immunohistochemical assay. Our results were analysed in relation to nuclear grade and other clinical and pathological parameters to see the possible correlation between the expression of MDR proteins and factors mentioned above. The majority of renal carcinoma specimens showed positivity for MDR proteins. In this regard, 21 % of samples revealed positive results for MDR1, 62 % for MRP1 and 76.6 % for LRP protein. Furthermore, our study displayed significant differences between MDR1, LRP and nuclear grade. On the other hand, no association was found between MRP1 and nuclear grade, as well as between the expression of three MDR proteins and other clinically relevant parameters.
Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Carcinoma de Células Renales/metabolismo , Resistencia a Antineoplásicos , Neoplasias Renales/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/biosíntesis , Partículas Ribonucleoproteicas en Bóveda/biosíntesis , Subfamilia B de Transportador de Casetes de Unión a ATP , Carcinoma de Células Renales/patología , Femenino , Humanos , Neoplasias Renales/patología , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVES: The aim of our work was to determine the expression of three MDR proteins (MDR1/Pgp, MRP1 and LRP/MVP) in 15 tissue samples of nephroblastoma (Wilms' tumour). BACKGROUND: The majority of Wilms' tumours respond well to chemotherapy and are successfully cured, but a small subset displays resistance to therapy. The molecular mechanisms of drug resistance in this tumour type of childhood are still poorly analyzed. In our opinion, the elucidation of reasons for therapy failure in nephroblastomas is urgently needed before cure becomes a reality for children with this cancer. METHODS: To demonstrate these proteins the enzyme indirect immunohistochemical method was used. The brown colour of the diaminobenzidine reaction product allowed us to define the distribution of stain clearly. CONCLUSION: Our immunohistochemical analysis did not demonstrate any expression of MDR1 in all cases of nephroblastoma (14 cases were after pre-operative chemotherapy, 1 case wasn't). The analysis of MRP1 and LRP expression in our set revealed 60% positivity for MRP1 and 26.7% positivity for LRP. The ability to recognize the multidrug resistance phenotype might assist in choosing specific chemotherapeutic regimens to improve prognosis and therapy (Tab. 2, Fig. 2, Ref. 20). Full Text (Free, PDF) www.bmj.sk.
Asunto(s)
Neoplasias Renales/química , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/análisis , Partículas Ribonucleoproteicas en Bóveda/análisis , Tumor de Wilms/química , Adulto , Preescolar , Resistencia a Antineoplásicos , Humanos , Inmunohistoquímica , Neoplasias Renales/tratamiento farmacológico , Tumor de Wilms/tratamiento farmacológicoRESUMEN
The aim of this work was to determine the expression of the multidrug resistance (MDR) proteins, namely MDR1 (P-glycoprotein), MRP1 (multidrug resistance-related protein) and LRP (lung resistance-related protein), in 87 samples of breast carcinoma. Detection of these proteins was provided by using indirect enzymatic immunohistochemistry. Our findings were compared with the other clinical and pathological parameters: expression of Her2/neu, estrogen receptor status (ER), progesteron receptor status (PR), histological grade and regional lymph node status. For statistical analysis, non-parametric two sided Mann-Whitney-U test was used. Majority of breast carcinoma specimens show positivity for these proteins. The MDR1 and MRP1 signal was found in the cytoplasm of cancer cells. The expression of LRP was detected in the cytoplasm close to the nuclear membrane. The samples were positive for MDR1 protein in 57%, for MRP1 in 84% and for LRP in 79%. Comparing our results with other clinical and pathological parameters, negative correlation between ER, PR and MDR1 expressions and histological grading status was found. No associations were observed between the MRP1 and LRP proteins and histological grading, as well as between the expression of three MDR proteins and the other clinically relevant parameters. In conclusion, high frequency of expression of MDR proteins in breast carcinoma cells suggests, that these proteins might be an important factor of drug resistance in breast carcinoma. Nevertheless, the negative correlation between the histological grade of malignancy of tumor and the expression of ER, PR and MDR1 indicates possible influence of progressive tumor cell de-differentiation. However, this finding has to be confirmed in additional evaluations.
Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/biosíntesis , Biomarcadores de Tumor/análisis , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática/patología , Pronóstico , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismoRESUMEN
Fifty lung cancer samples (41 non-small cell lung cancer-NSCLC and 9 small cell lung cancer-SCLC) were immunohistochemically analyzed for lung resistance-related protein (LRP) and multidrug resistance-associated protein 1 (MRP1) expressions which were then correlated with histopathological subtype of the tumor. To detect these proteins, monoclonal antibodies LRP-56 and MRPm6 were used. NSCLC samples were divided into two groups, adenocarcinomas (17 samples) and squamous cell carcinomas (24 samples). Four categories of LRP and MRP1 quantity were distinguished: +++ = high level--90--100% of positive cells, ++ = lower level--10--90% of positive cells, + = low level--up to 10% of positive cells, - = negative cells--0% of positive cells. Within the NSCLC group the most samples (36/41) had the similar level of LRP and MRP1. Significantly higher expression of both proteins was observed in the adenocarcinomas in comparison with squamous cell carcinomas. The lowest positive staining for LRP and MRP1 proteins has been found in SCLC. It is suggested that our finding can confirm the overall empirical clinical knowledge about much higher chemosensitivity of untreated SCLC comparing to NSCLC.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Pequeñas/tratamiento farmacológico , Carcinoma de Células Pequeñas/genética , Resistencia a Múltiples Medicamentos , Perfilación de la Expresión Génica , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/biosíntesis , Anticuerpos Monoclonales , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Pequeñas/patología , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/patologíaRESUMEN
In this study we describe the localization of MRP1 in normal and hyperplastic thyroid tissues. To demostrate this protein we have used the enzyme imunohistochemical method with monoclonal antibody MRPm6. We have found MRP1 to be present in follicular epithelial cells of normal thyroid tissue and higher expression in the same cells of hyperplastic thyroid tissue. The brown colour of the diaminobenzidine reaction product allowed us to define the distribution of stain clearly. (Fig. 4, Ref. 16.)
Asunto(s)
Proteínas Asociadas a Resistencia a Múltiples Medicamentos/análisis , Glándula Tiroides/química , Bocio/metabolismo , Humanos , Hiperplasia , Inmunohistoquímica , Glándula Tiroides/patologíaRESUMEN
In this study, we have determined the LRP (lung resistance-related protein) by immunohistochemical method. LRP belongs to proteins which cause the multidrug resistance (MDR). It has been found in various normal human tissues, where it plays a protective role against toxic compounds. Multidrug-resistant cells distribute the cytotoxic drug into the perinuclear region and then redistribute it back into the cytoplasm. It is just a hypothesis today that LRP can mediate drug resistance by regulating both the cytoplasmic redistribution and the nucleocytoplasmic transport of drugs. In order to detect LRP we have used the paraffin-embedded sections of the normal human lung tissue. LRP was predominantly located in two regions: 1) in bronchial epithelial cells and 2) in alveolar macrophages. Positive cells were coloured brown and showed strong reactivity. Negative control included the omitting of primary antibody and replacing it by buffer solution. Bronchial epithelial cells and alveolar macrophages stayed uncoloured, i.e. unreactive. (Fig. 5, Ref. 17.).