NM23 gene expression in human breast carcinomas: loss of correlation with cell proliferation in the advanced phase of tumor progression

NM23 is a protein associated with tumor progression, expressed in all tissues and in human tumors. Reduced expression of NM23.H1 is related to high incidence of lymph node and distant metastasis or to poor prognosis of the patient in several human malignant tumors. In this study we analyze NM23 expression in non-neoplastic mammary tissues surrounding the tumoral lesions, in human mammary carcinomas and in lymph node metastasis. Our analysis shows that NM23.H1 expression is lower in the mammary cells surrounding the tumor than in the tumor itself. In the primary tumors we observed a negative trend between degree of local invasion and level of NM23.H1 expression. A further decrease of NM23.H1 was detected in the invasive tumors that metastasized to axillary lymph nodes and in the metastasis. NM23.H2 was always more highly expressed than NM23.H1, and reduced expression of NM23.H1 but not NM23.H2 was concordant with the presence of lymph node metastasis or local invasiveness of the primary tumor. A positive correlation between NM23.H1 mRNA content and cell growth rate of breast tumor cells has been confirmed. However, this trend was not maintained in cancer cells from tumors that metastasized to axillary lymph nodes and in metastatic cells; in these 2 situations the NM23.H1 mRNA content varied without any relationship to the proliferative rate of the cells. In addition, in comparison with the initial tumor, the metastatic cell population showed a strong decrease of NM23.H1 expression and increased proliferative activity.

67-Kilodalton laminin receptor expression correlates with worse prognostic indicators in non-small cell lung carcinomas

Tumor samples obtained from 72 patients resected for non-small cell lung cancer were stained immunohistochemically using an immunoperoxidase method and the MLuC5 monoclonal antibody specific for the 67-kDa laminin receptor. Sixty-one of 72 patients (84.7%) displayed a MLuC5-positive reaction, which was usually localized in both the inner surface of the plasmatic membranes and the cytoplasm of neoplastic cells. When we compared the laminin receptor expression with clinicopathological and biological parameters such as histotype, grading, T status, N status, ploidy, proliferative activity, vessel invasion, and p53 protein accumulation, the following results were observed: (a) the mean expression of the receptor was higher in the group of patients with metastatic nodal involvement than in those with uninvolved lymph nodes (P = 0.02); (b) a high Ki-67 score (>13% of positive cells) was observed in tumors with a higher mean value of laminin receptor (P = 0.004); (c) the tumors harboring neoplastic emboli in their vessels showed a higher laminin receptor immunoreactivity (P = 0.02); and (d) a borderline association was found between the high mean value of laminin receptor immunopositivity and p53 accumulation in neoplastic cell nuclei (P = 0.05). Our observations indicate that detection of high tissue levels of 67-kDa laminin receptor is associated with an invasive phenotype in non-small cell lung cancer and may provide further information in the biological characterization of this type of cancer.

Further characterisation of [3H]8-hydroxy-2-(di-N-propylamino)tetralin binding sites in human brain postmortem

The saturation parameters and the pharmacological characteristics of the binding of the serotonin 1A (5-HT1A) receptor agonist [3H]8-hydroxy-2-(di-N-propylamino)tetralin ([3H]8-OH-DPAT), as well as the effects of nucleotides and divalent cations (Mg2+, Mn2+) on it, were compared in some human postmortem brain regions: the main cortical areas, hippocampus and striatum. [3H]8-OH-DPAT labelled a single population of recognition sites with the highest maximal capacity (Bmax) in the hippocampus and the lowest affinity in the striatum. Among the various cortical areas, the frontal cortex exhibited the highest Bmax. The pharmacological profile of the [3H]8-OH-DPAT binding sites was consistent with the labelling of the 5-HT1A receptor in the hippocampus and cortex, whereas the striatal site shared strong similarity to the presynaptic serotonin transporter. Modulation of [3H]8-OH-DPAT binding by divalent cations and nucleotides was detectable and stable in autopsy brains. In particular, nucleotide effects were area-dependent: guanosine thiotriphosphate (GTP gamma S) reduced [3H]8-OH-DPAT binding to the same extent in the hippocampus and frontal cortex, while having no effect in the striatum. Divalent cation effects depended also upon the brain area: in the striatum, they inhibited [3H]8-OH-DPAT binding, while stimulating it in the hippocampus and, with less extent, in the frontal cortex. In summary, these findings suggest that the [3H]8-OH-DPAT binding and its modulatory parameters in human brain tissues seem to show similarities but also some differences with respect to those determined in the rat brain. Furthermore, postmortem stability of GTP and divalent cation sensitive 5-HT1A receptors underlines the need for further studies on the regulatory and functional properties of this receptor in the human brain.

The progestin ORG2058 but not retinoic acid stimulates BRCA1 mRNA expression in MCF-7 human breast cancer cells

BRCA1 has been characterized as one of the major breast cancer susceptibility genes. Although no BRCA1 mutations have been reported in sporadic breast cancer, altered levels of BRCA1 are found in non hereditary breast malignant lesions. Therefore, BRCA1 is potentially playing a key role in the genesis of breast cancer. In this study, we explored the effects of estradiol and two differentiating agents, the progestin ORG2058 and retinoic acid, on BRCA1 mRNA expression in human estrogen and progesterone receptor positive MCF-7 cells. Using RNAse protection assay, we have demonstrated that ORG2058 induces a major (50 times) stimulation of BRCA1 mRNA expression. The maximum induction effect was obtained at the pharmacological dose of 100 nM and after 48 h of treatment. While estradiol generated an expected increase of BRCA1 mRNA, retinoic acid did not produce any effects. Our results demonstrate for the first time that BRCA1 is specifically up-regulated by a progestin, a steroid known to induce the differentiation of epithelial mammary cells. The absence of retinoic acid effect suggests that a specific progesterone-dependent pathway, could control BRCA1 expression.

Alterations of P16 (MTS1) in node-positive non-small cell lung carcinomas

The status of the P16 gene was investigated by Southern blot, polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP), and DNA sequencing analyses in 30 primary resected non-small cell lung carcinomas (NSCLCs) with metastatic involvement of thoracic lymph nodes and 33 NSCLCs without node metastases. Direct sequencing of tumour DNA samples scored positive by PCR-SSCP showed five somatic mutations of the P16 gene: four nonsense and one frameshift. The Southern blot analysis revealed the presence of a homozygous deletion of the P16 locus in one tumour. All of the six NSCLCs with somatic aberrations of the P16 gene belonged to the series of tumours with metastatic diffusion to thoracic lymph nodes. In each of these six cases, the genetic aberration was seen in both the primary tumour and the node metastasis. No P16 alteration was found in tumours without metastatic lymph nodes. This difference was statistically significant (P = 0.02). No correlation was present between P16 alterations and other clinicopathological parameters including age of patients, tumour size, histological type, and grade. In three tumours with genetic aberration of P16, there was a concomitant alteration of the p53 gene. Our results indicate that the P16 gene is infrequently mutated (10 per cent of the cases examined) in primary resected NSCLC. However, since P16 mutations were found only in metastatic tumours, they may be important events in late phases of tumour progression and could represent useful markers of tumour aggressiveness in NSCLC.

Evolution of respiratory mechanics in preterm babies after surfactant administration in the neonatal period

OBJECTIVE

To evaluate the development of the lung of preterm infants given exogenous surfactant in the neonatal period versus control babies through the evolution of respiratory mechanics (RM) parameters.

PATIENTS AND METHODS

Retrospective analysis of babies < or = 30 weeks' gestation admitted to our intensive care unit in the period 1990-94 in which RM parameters had been followed for the first two years of life. Babies were divided into two groups depending on the fact that they received endotracheal porcine surfactant 200 mg/kg for prophylaxis or rescue treatment of respiratory distress syndrome (RDS) (treatment group, No.37) or not (control group, No.41). Evaluation of RM were performed by means of PèDS at the post-conceptual age of 38-42 wks and/or 3-6 mth and/or 9-12 mth and/or 18-24 mth in spontaneous breathing after sedation with chloral hydrate and positioning of an oesophageal balloon. Chronic lung disease (CLD) was defined a posteriori as presence of polypnea at discharge independently from oxygen-therapy and from radiological findings, including also the most severe forms of bronchopulmonary dysplasia.

RESULTS

The treatment and control group did not differ for birth weight and gestational age (1060 +/- 293 vs 1189 +/- 321 g. and 28.1 vs 28.3 +/- 1.5 wks respectively), however the babies of the treatment group had higher incidence of RDS, mechanical ventilation, nasal continuous positive airway pressure, and use of caffeine (p < 0.01 vs the control group). No difference was found in the incidence of CLD at discharge between the two groups. No difference was found between the treatment and the control group at the various times of the examinations concerning respiratory frequency, tidal volume, minute ventilation, dynamic compliance of the respiratory system (indexed both to body weight and length), and respiratory system resistances. The above cited parameters, except respiratory system resistances, showed significant changes from the first to the last evaluation (p < 0.01) in both groups, indicating a continuous improvement of the RM properties of the lung in the first two years of life. As regards respiratory system resistances, these were significantly reduced in the first two years of life in the treatment group (from 73.9 +/- 38.5 to 31.3 +/- 5.8 cmH2O/L/sec; p < 0.05), while there was no significant improvement in the control group (from 65.1 +/- 26.1 to 42.8 +/- 41.6 cmH2O/L/sec; p = ns).

CONCLUSION

The use of surfactant both as prophylactic and rescue treatment of RDS seems able to guarantee the lung of the preterm infant to develop in a regular way, in spite of high incidence of respiratory diseases and unfavourable effects of respiratory therapies. This study also allows to have standard reference values of RM parameters for ex-preterm infants in the first two years of life to evaluate their lung development.

Evaluation of reactive oxygen metabolites with micromethod in neonates: determination of standards of normality in full-term babies

We have evaluated the value of reactive oxygen metabolites (ROMs) in 98 full-term neonates at 72 +/- 6 hours of life with a new colorimetric simple and rapid method (d-ROMs Test, Diacron s.r.l.) to establish the normal values for infants. The mean value of ROMs we have obtained in the total of the population was 127.9 +/- 39.2 U.Carr. We have then considered subgroups of infants on the basis of vaginal delivery vs cesarean section, and asphyxia vs non asphyxia during the delivery. We have found no difference within these groups and between the subgroups and the total population for the value of ROMs. We have preferred to consider as reference value for normality that of babies without intrapartum asphyxia, independently of the mode of delivery. This value is 125.2 +/- 27.6 U.Carr. The value of normality for full-term infants is lower than that reported for adults (between 250-300 U.Carr). This can be interpreted as a particular response of full-term baby to oxidative stress.

Neoangiogenesis and p53 protein in lung cancer: their prognostic role and their relation with vascular endothelial growth factor (VEGF) expression

Following up-regulation of an angiogenesis inhibitor by the wild-type p53 protein proven recently, we have analysed on the one hand the prognostic impact of microvessel count (MC) and p53 protein overexpression in non-small-cell lung carcinoma (NSCLC) progression and, on the other hand, the inter-relation between the microvascular pattern and the p53 protein expression. Moreover, we assessed the expression of vascular endothelial growth factor (VEGF), one of the pivotal mediators of tumour angiogenesis, in order to investigate its relation to p53 protein expression and MC. Tumours from 73 patients resected for NSCLC between March 1991 and April 1992 (median follow-up 47 months, range 32-51 months) were analysed using an immunohistochemical method. In univariate analysis, MC and p53 accumulation were shown to affect metastatic nodal involvement, recurrence and death significantly. Multiple logistic regression analysis showed an important prognostic influence of MC and nodal status on overall (P = 0.0009; P = 0.01) and disease-free survival (P = 0.0001; P = 0.03). Interestingly, a strong statistical association was observed between p53 nuclear accumulation and MC (P = 0.0003). The same inter-relationship was found in non-squamous histotype (P = 0.002). When we analysed the concomitant influence of MC and p53 expression on overall survival, we were able to confirm a real predominant role of MC in comparison with p53. With regard to VEGF expression, p53-negative and lowly vascularized tumours showed a mean VEGF expression significantly lower than p53-positive and highly vascularized cancers (P = 0.02). These results underline the prognostic impact of MC and p53 protein accumulation in NSCLC and their reciprocal inter-relationship, supporting the hypothesis of a wild-type p53 regulation on the angiogenetic process through a VEGF up-regulation.

p53 alterations are predictive of chemoresistance and aggressiveness in ovarian carcinomas: a molecular and immunohistochemical study

Chemotherapeutic management of ovarian cancers is a difficult task as these neoplasms show significant differences in chemosensitivity, even if they share identical clinicopathological features. The present study was undertaken to investigate the prognostic and predictive role of p53 alterations in ovarian cancer. To this end, using different technical approaches, i.e. genetic and immunohistochemical analyses, we analysed a series of 68 ovarian neoplasms including 15 low malignant potential (LMP) tumours and 53 invasive carcinomas. We never observed p53 abnormalities in LMP tumours. p53 alterations were present only in invasive ovarian carcinomas, and they were detected much more frequently in tumours characterized by high histological grade (P = 0.01) and advanced-stage disease (P = 0.006 and P = 0.05 for gene mutations and protein expression respectively). For 33 patients with invasive ovarian cancer, information was available concerning response to cisplatin-based chemotherapy. A strong correlation (P = 0.001) has emerged between p53 alterations and response to chemotherapy; only one (14%) of seven patients who had a pathological complete response to antiblastic drugs showed p53 aberrations, whereas 18 (82%) of 22 cases with partial response and all of the four non-responsive patients scored positive for p53 abnormalities. We also observed that patients with p53 mutations had a significantly shorter progression-free survival than patients with p53-negative tumours (P = 0.05). Taken together, our results strongly suggest that in epithelial ovarian malignancies tumours showing p53 aberrations are significantly less sensitive to chemotherapy and more aggressive than those with functional p53. Thus, a routine analysis of this gene could have profound implications for the treatment of ovarian cancer.

Preoperative serum antibodies against the p53 protein in patients with ovarian and endometrial cancer

Antibodies against the p53 protein were measured with a sandwich-type enzyme-linked immunosorbent assay in blood samples preoperatively collected from 30 patients with ovarian cancer and 30 patients with endometrial cancer. Anti-p53 antibodies were detected in 33.3% of patients with ovarian cancer, comprising 22.2% of the 9 patients with stage I-II disease, 30.8% of the 13 patients with stage III disease, and 50.0% of the 8 patients with stage IV disease. Anti-p53 antibodies were found in none of the 4 patients with well differentiated tumors and in 38.5% of the 26 patients with moderately or poorly differentiated tumors. Among the 21 patients with stage III-IV disease, a complete clinical response to front-line platinum-based chemotherapy was obtained by 46.2% of the 13 patients without anti-p53 antibodies and 25.0% of the 8 patients with anti-p53 antibodies. Antibodies against the p53 protein were detected in only 6.7% of patients with endometrial cancer. The low incidence of anti-p53 antibodies in patients with endometrial cancer seems to suggest that the serum assay of these autoantibodies has a limited clinical relevance in the management of this malignancy. On the other hand in patients with ovarian cancer the incidence of serum anti-p53 antibodies is relatively high, and, moreover, it seems to increase with tumor stage and grade and seems to be associated with a lower response rate to chemotherapy. However, the small number of patients did not allow us to obtain statistically significant differences.

BRCA1 germline mutational spectrum in Italian families from Tuscany: a high frequency of novel mutations

BRCA1 germline mutations confer susceptibility to familial breast and ovarian cancer. Mutational hot spots have never been detected in BRCA1 cDNA. Some mutations have been reported several times whereas some others appear to be population-related. In this study a group of 36 Italian families were analysed for BRCA1 germline mutations. All of them were screened by allele-specific oligonucleotide hybridization (ASO) for three recurrent mutations (185delAG, 5382insC, nt332-T>G). Twenty families, selected because of their high risk of carrying BRCA1 mutations, were subjected to analysis of the entire coding sequence of the gene. A total of eight mutations were found. ASO screening demonstrated only one known mutation in one patient, whereas cycle sequencing revealed five new mutations. Three of these new mutations were frameshifts: one occurred in exon 11 (1499insA), one in exon 16 (4873delCA) and one in the splice site of exon 3 (252delAAgt). Two were missense mutations (Cys64Arg; Asn158Tyr). The same frameshift mutation, 1499insA, was detected in three unrelated families. Haplotype analysis supported the hypothesis that two of these families may have had common ancestors, whereas in the third family the analysis was uninformative. BRCA1 germline mutations were found in one out of two families with ovarian cancer, in five out of eight families with breast-ovarian cancer, and in two out of 11 families with breast cancer. All three families with 1499insA mutations included at least one case of ovarian cancer. The majority of the ovarian cancers (4/5) associated with detectable BRCA1 germline mutations were of serous histotype.

Expression of the Mr 67,000 laminin receptor is an adverse prognostic indicator in human thyroid cancer: an immunohistochemical study

Increased expression of the Mr 67,000 laminin receptor (LR) is a consistent event which appears as cancer cells acquire an invasive and metastatic phenotype. The Mr 67,000 LR is one of the many laminin-binding proteins able to interact with the major glycoprotein of basement membranes, laminin. The recent development of a specific monoclonal antibody directed against the Mr 67,000 LR MLuC5 has allowed us to study large retrospective groups of human cancers with the aim of correlating the Mr 67,000 LR expression to the clinical, pathological, and survival data of the patients. A significant correlation has already been established between the increased expression of Mr 67,000 LR and survival of patients with breast, colon, ovary, lung, and endometrial cancers. In this study, we investigated the possibility that the detection of Mr 67,000 LR in thyroid human cancers could also be of prognostic value. We analyzed the expression of Mr 67,000 LR with immunohistochemistry using MLuC5 antibodies in paraffin sections of 40 benign and 170 malignant thyroid human tumors. We found that Mr 67,000 LR was not usually detectable in normal thyroid tissues adjacent to the lesion. Only 3 of the 40 thyroid adenomas examined (7.5%) presented cells positive for Mr 67,000 LR. For the malignant thyroid tumors examined, we found that 22.3% of papillary thyroid carcinomas, 38% of follicular thyroid carcinomas, 40% of poorly differentiated carcinomas, 25% of medullary carcinomas, and 58.3% of anaplastic carcinomas expressed a high level of Mr 67,000 LR. Although no correlation between the Mr 67,000 LR expression and survival was found in patients with follicular thyroid carcinomas, papillary thyroid carcinomas, anaplastic carcinomas, and medullary carcinomas, there was a significant correlation in primary thyroid cancers. Our data represent the first extensive study of the Mr 67,000 LR expression in human thyroid cancers and strongly suggest that its detection could be of prognostic value in the investigation of primary thyroid cancers.

Prognostic significance of tumoral angiogenesis in completely resected late stage lung carcinoma (stage IIIA-N2). Impact of adjuvant therapies in a subset of patients at high risk of recurrence

BACKGROUND

Angiogenesis plays a critical role in human tumor growth and metastasis. Microvessel count (MC), as a measure of tumor angiogenesis, has been significantly correlated with metastatic disease in cutaneous, mammary, prostatic, head and neck, and early stage lung carcinoma.

METHODS

Ninety-six consecutive patients affected by T1-3N2MO nonsmall cell lung carcinoma (NSCLC), who underwent radical surgery between March 1991 and March 1995 (in many cases followed by adjuvant therapies) were prospectively investigated to assess the prognostic significance of both traditional and new biologic parameters like proliferative activity, blood vessel invasion by tumoral cells, and neovascularization (estimated by the MC).

RESULTS

With a median follow-up of 24 months, the projected 3-year survival was 42.1%. Forty-eight of the patients (50%) had already experienced a local (n=14) or systemic (n=34) relapse. The extent of resection (lobectomy vs. pneumonectomy; P=0.0045), the number of mediastinal lymph node levels (single vs. multiple; P=0.014), and the MC (on a X200 field; P=0.015) correlated significantly with metastatic disease. By univariate analysis, significant predictors of survival were: the extent of surgery (P=0.03), adjuvant therapy (P=0.05), and MC (< or = vs. > cut-off; P=0.00076). On multivariate analysis, however, only the MC (P=0.02) retained its level of prognostic significance.

CONCLUSIONS

Our results provide evidence that neovascularization, estimated by the MC, can predict metastatic disease and survival in patients with completely resected T1-3N2M0 NSCLC, and may also be useful in patient selection for effective adjuvant treatment.

Neoangiogenesis: a putative marker of malignancy in non-small-cell lung cancer (NSCLC) development

Several studies have documented a relevant prognostic role of microvessel count (MC) in non-small-cell lung carcinomas (NSCLC). However, no evidence has been reported about the involvement of neo-angiogenesis in the development of bronchial cancers. The aim of this study was to analyze microvessel density both in normal and in pathological features of the bronchial tree detected concomitantly with carcinomas. In a group of 34 patients resected for NSCLC, 48 bronchial lesions (hyperplasia, squamous metaplasia, moderate dysplasia and in situ carcinoma) were identified. In addition, 20 samples of normal bronchial epithelium from the same patients were analyzed. A monoclonal antibody was used in order to identify microvessels in the most intense areas of neovascularization from the bronchial specimens. MC was also analyzed in invasive components. An increased number of microvessels was observed from normal to dysplastic epithelium, including in situ carcinoma. Mean MC was significantly lower in normal, hyperplastic and squamous metaplastic epithelium than in dysplastic epithelium and in situ carcinoma. In particular, no differences were observed between normal and hyperplastic/metaplastic components, whereas a statistically significant difference appeared between the latter and dysplastic lesions. Moderate dysplasia and in situ carcinoma showed a number of microvessels in the lamina propria of their mucosa which were not significantly different from the invasive component, whereas hyperplastic/metaplastic lesions presented a much lower number of microvessels than invasive cancer. From these data it appears that normal bronchial epithelium and lesions associated with cancers of the bronchial tree show neovascularization in their stromal component. Hyperplasia and squamous metaplasia, unlike dysplasia and in situ carcinoma, show a low microvessel count, and they cannot represent precursor or incipient changes in the bronchial epithelium before the fully developed in situ stage has also been reached.

Prognostic significance of tumoral angiogenesis in completely resected late stage lung carcinoma (stage IIIA-N2). Impact of adjuvant therapies in a subset of patients at high risk of recurrence

BACKGROUND

Angiogenesis plays a critical role in human tumor growth and metastasis. Microvessel count (MC), as a measure of tumor angiogenesis, has been significantly correlated with metastatic disease in cutaneous, mammary, prostatic, head and neck, and early stage lung carcinoma.

METHODS

Ninety-six consecutive patients affected by T1-3N2MO nonsmall cell lung carcinoma (NSCLC), who underwent radical surgery between March 1991 and March 1995 (in many cases followed by adjuvant therapies) were prospectively investigated to assess the prognostic significance of both traditional and new biologic parameters like proliferative activity, blood vessel invasion by tumoral cells, and neovascularization (estimated by the MC).

RESULTS

With a median follow-up of 24 months, the projected 3-year survival was 42.1%. Forty-eight of the patients (50%) had already experienced a local (n=14) or systemic (n=34) relapse. The extent of resection (lobectomy vs. pneumonectomy; P=0.0045), the number of mediastinal lymph node levels (single vs. multiple; P=0.014), and the MC (on a X200 field; P=0.015) correlated significantly with metastatic disease. By univariate analysis, significant predictors of survival were: the extent of surgery (P=0.03), adjuvant therapy (P=0.05), and MC (< or = vs. > cut-off; P=0.00076). On multivariate analysis, however, only the MC (P=0.02) retained its level of prognostic significance.

CONCLUSIONS

Our results provide evidence that neovascularization, estimated by the MC, can predict metastatic disease and survival in patients with completely resected T1-3N2M0 NSCLC, and may also be useful in patient selection for effective adjuvant treatment.

Bronchioloalveolar lung carcinomas: K-ras mutations are constant events in the mucinous subtype

Bronchioloalveolar carcinoma (BAC) is a form of peripheral lung adenocarcinoma growing as a single layer of malignant cells along the walls of terminal airways. The existence of BAC as a separate clinico-pathological entity has been a matter of controversy, mainly because its histogenesis is uncertain and it is not easily distinguishable from conventional lung adenocarcinoma (CLA). Three subtypes of BAC have been described using histological and cytological criteria: mucinous, non-mucinous, and sclerosing. The clinical behaviour of BAC appears to be dependent on the histological subtype. The different morphological patterns and clinical outcome of the subtypes of BAC suggest that their biological behaviour may be different from one another and from CLA. This study has investigated 58 BACs (10 mucinous, 40 non-mucinous, and 8 sclerosing) and 50 control CLAs for mutations at codon 12 of the K-ras oncogene. Twenty-one (36 per cent) BACs and 13 (26 per cent) CLAs showed K-ras mutations. A clear association (P < 0.0001) between K-ras mutations and the mucinous type of BAC was observed: all 10 mucinous tumours examined were scored positive for mutations in the K-ras gene, while only 9 (23 per cent) of the 40 non-mucinous and 2 (25 per cent) of the 8 sclerosing BACs were found to be positive. The frequency of ras mutations in non-mucinous BAC, sclerosing BAC, and CLA was not statistically different. Our data indicate that BACs are a heterogeneous group of lung tumours and that the mucinous form might represent a biological entity separate from both the other two BAC types and CLA.

p21WAF1 immunohistochemical expression in breast carcinoma: correlations with clinicopathological data, oestrogen receptor status, MIB1 expression, p53 gene and protein alterations and relapse-free survival

p21 protein (p21) inhibitor of cyclin-dependent kinases is a critical downstream effector in the p53-specific pathway of growth control. p21 can also be induced by p53-independent pathways in relation to terminal differentiation. We investigated p21 immunoreactivity in normal breast and in 91 breast carcinomas [three in situ ductal carcinomas (DCIS) with microinfiltration and 88 infiltrating carcinomas, 17 of which with an associated DCIS; 57 node negative and 34 node positive] with long-term follow-up (median = 58 months). Seven additional breast carcinomas with known p53 gene mutations were investigated. In normal breast p21 expression was seen in the nuclei of rare luminal cells of acinar structures, and in occasional myoepithelial cells. Poorly differentiated DCIS showed high p21 expression, whereas well-differentiated DCIS tumours showed few p21-reactive cells. p21 was seen in 82 (90%) infiltrating tumours; staining was heterogeneous; the percentage of reactive nuclei ranged from 1% to 35%. High p21 expression (more than 10% of reactive cells) was seen in 24 (26%) cases, and was associated with high tumour grade (P = 0.032); no associations were seen with tumour size, metastases, oestrogen receptor status, MIB1 expression and p53 expression. p21 expression in cases with p53 gene mutations was low in six cases and high in one. High p21 expression was associated with short relapse-free survival (P = 0.003).

Recurrence and death in non-small cell lung carcinomas: a prognostic model using pathological parameters, microvessel count, and gene protein products

The 5-year survival rate of non-small cell lung carcinoma (NSCLC) has only marginally improved during the past two decades, despite advances in surgery and chemoradiotherapy. Major efforts are currently directed toward biological characterization of these tumors to define biomarkers able to add further prognostic information, thus improving new therapeutic protocols. We analyzed the predictive relevance of the microvessel count (MC), bcl-2 and p53 proteins, proliferative activity, and usual postsurgical parameters on recurrence and overall survival in a series of 70 patients with NSCLC. The expression of biological parameters (p53, bcl-2, proliferative activity, and MC) was detected using immunohistochemistry on paraffin-embedded and frozen sections from the tumors treated with surgical resection alone until relapse. In the univariate analysis, the histotype, tumor status, node status, p53, bcl-2, and MC have been shown to significantly affect progression and death. In the multiple logistic regression analysis, the MC (P < 0.000001), tumor status (P < 0.005), and node status (P < 0.0002) influenced the overall survival while prediction of relapse was strongly revealed by tumor status (P < 0.005), nodal metastatic involvement (P < 0.000001), and the assessment of the vascular count (P < 0.0004). These data have allowed the creation of a multivariate model which may add more information on risk of recurrence and death in patients with NSCLC and can form the basis for future randomized clinical trials.

p21 RNA and protein expression in non-small cell lung carcinomas: evidence of p53-independent expression and association with tumoral differentiation

p21, the product of the WAF1/CIP1/SDI1/mda-6 gene, is an inhibitor of cyclin-dependent kinases. In cell cultures p21 is induced by p53-dependent and p53-independent pathways by DNA damage and induction of differentiation. We investigated p21 RNA and immunohistochemical expression in 43 non-small cell lung carcinomas and corresponding normal lung samples previously investigated for p53 and WAF1 gene status and p53 protein expression. p21 RNA and protein expression in normal and neoplastic tissues were strictly associated (p-0.0001). In normal tissue p21 RNA was expressed at low levels and p21 immunoreactivity was seen in scattered differentiated bronchial, alveolar and stromal cells. In the majority of neoplasms p21 protein and RNA were expressed at higher levels than in the corresponding normal tissues: p21 overexpression was seen in 27 (63%) and 28 (65%) cases respectively. p21 was expressed independently from p53 gene/protein alterations. p21 overexpression was more frequent in well differentiated tumors (P=0.01 and P=0.022 for RNA and protein respectively), and p21 immunoreactivity was usually seen in foci of more pronounced differentiation. We conclude that p21 expression is related to tumor differentiation, and that p53-independent p21 expression is a common feature of in vivo neoplasms.

Down regulation of NM23.H1, NM23.H2 and c-myc genes during differentiation induced by 1,25 dihydroxyvitamin D3

The NM23 gene, involved in the negative regulation of metastatic progression, has been found to be highly homologous to developmentally regulated genes such as the awd gene in Drosophila melanogaster and the Gip17 gene in Dyctiostelium discoideum. To ascertain whether the NM23 genes are involved in the differentiation processes of human cell lines, the NM23.H1 and NM23.H2 expression level has been determined during the monocyte-macrophage differentiation of HL-60 and U-937 cell lines induced by vitamin D3. In both lines, vitamin D3 produced induction of differentiative markers, inhibition of cell proliferation and a decrease of the NM23.H1, NM23.H2 and c-myc genes, behaving both as a differentiative and an antiproliferative agent. The fact that the c-myc transcriptional factor PuF is identical to the NM23.H2 gene and that NM23 protein could be a transcriptional factor suggests that the regulatory action exerted by vitamin D3 on c-myc transcription is mediated by NM23.H2.

bcl-2, p53 and proliferating cell nuclear antigen expression is related to the degree of differentiation in thyroid carcinomas

Thyroid carcinomas are heterogeneous in terms of histology, clinical presentation, treatment response and prognosis. Since bcl-2 and p53 gene alterations are frequently involved in both lymphoid and epithelial malignancies, we analysed the expression of bcl-2, p53 and proliferating cell nuclear antigen (PCNA) in a group of 134 patients with thyroid neoplasms. The same markers were evaluated in fetal and adult normal thyroids as well as in 40 benign lesions. The study was carried out by immunocytochemistry on archival material using antibodies against bcl-2 and p53 protein on tissue sections of 40 adenomas (As), 20 medullary carcinomas (MCs), 70 well-differentiated carcinomas (WDCs), 20 poorly differentiated carcinomas (PDCs) and 24 undifferentiated carcinomas (UCs). bcl-2 immunoreactivity was detected in 36 out of 40 (90%) As, 20 out of 20 (100%) MCs, 60 out of 70 (85.7%) WDCs, 20 out of 20 (100%) PDCs, and 8 out of 24 (33.3%) of UCs. p53 expression was present in 11.4% of WDCs, 5% of PDCs, 5% of MCs and 62.5% of UCs. By contrast, no p53 immunoreactivity was detected in 40 adenomas and in all the normal thyroid tissues studied. We observed a positive correlation between the expression of p53 and PCNA (r = 0.42; P = 0.035) in a group of UCs, but not in WDCs, PDCs and MCs. Neither p53 nor bcl-2 expression were correlated with clinicopathological parameters, such as age, sex, pTNM and survival. Our results suggest that in tumours of the follicular epithelium p53 and bcl-2 protein abnormalities are associated with more advanced carcinomas and especially with undifferentiated carcinomas, while they are only rarely altered in tumours of the parafollicular C cells.