Assessment of the prognostic relevance of serum anti-p53 antibodies in epithelial ovarian cancer

The objective of this study was to assess the prognostic relevance of preoperative serum anti-p53 antibodies in epithelial ovarian cancer. These autoantibodies were detected with a new generation enzyme-linked immunosorbent assay in blood samples preoperatively drawn from 86 patients with this malignancy. Serum anti-p53 antibodies were found in 3 (10.0%) of the 30 patients with stage I-II and 15 (26.8%) of the 56 patients with stage III-IV epithelial ovarian cancer (P = 0.09). We assessed in detail 44 patients with stage III-IV disease who underwent six cycles of first-line platinum-based chemotherapy. A pathological complete response at second-look was achieved by none of the 15 patients with serum anti-p53 antibodies compared to 24.1% of the 29 patients without autoantibodies (P = 0.09). However, the preoperative serum anti-p53 antibody status had no prognostic relevance for progression-free survival and survival. In conclusion, the assessment of preoperative serum anti-p53 antibodies seems to have a limited clinical value in the management of patients with advanced epithelial ovarian cancer.

Microsatellite alterations and p53, TGFbetaRII, IGFIIR and BAX mutations in sporadic non-small-cell lung cancer

Fifty-two sporadic primary non-small-cell lung carcinomas (NSCLC) were examined for microsatellite instability. Six different microsatellite markers localized on chromosomes 2, 5, 8, 10, 11 and 17 were used. Genomic instability was observed in 35% (18/52) of NSCLC at single or multiple loci. The tumors were also analyzed for p53-gene mutations by PCR-SSCP analysis. Polynucleotide stretch frameshift mutations of TGFbetaRII (transforming-growth-factor-beta receptor II), IGFIIR (insuline growth-factor II receptor) and BAX genes were also analyzed. RER+ (replication-error-positive) tumors appear not to be affected by a higher rate of point mutations in coding sequences: no correlation was found between microsatellite instability and point mutations in the p53 gene, and the RER+ tumors showed no alterations in stretches of nucleotide inside TGFbetaRII, BAX or IGFIIR.

Primary chemotherapy in locally advanced breast cancer (LABC): effects on tumour proliferative activity, bcl-2 expression and the relationship between tumour regression and biological markers

The rate of tumour cell proliferation evaluated by the [3H]-thymidine labelling index ([3H]-dT-LI) is known to be an independent prognostic factor in patients with operable breast cancer and significantly predicts the response to chemotherapy in patients with advanced disease. In locally advanced breast cancer (LABG), we examined whether chemotherapy induced modifications in [3H]-dt-LI, and bcl-2 expression and their relationship with tumour regression and prognosis. 70 LABC patients received three courses of primary chemotherapy (FEC: 5-fluorouracil 600 mg/m2, epidoxorubicin 60 mg/m2, cyclophosphamide 600 mg/m2, followed by surgery and subsequent adjuvant chemotherapy consisting of three courses of FEC alternated with three courses of CMF (cyclophosphamide 600 mg/m2, methotrexate 40 mg/m2, 5-fluorouracil 600 mg/m2). Tumour biological markers were evaluated on diagnostic biopsy, before primary chemotherapy and at surgery. Tumour cell proliferation was determined by [3H]-dT-LI, whilst bcl-2 expression was examined by immunohistochemical staining. The overall response rate to primary FEC was 74.3% (95% confidence interval 57.6-83.2%). The response rate correlated with high [3H]-dT-LI: 88% (29/33) of patients with high [3H]-dT-LI achieved an objective response compared with 62% (23/37) of patients with low [3H]-dT-LI (P = 0.014). The 3 patients achieving a pathological complete response after induction treatment had high proliferative tumours. The highest 2-year relapse free survival (66.6%) was observed in patients with low [3H]-dT-LI after primary chemotherapy. The median bcl-2 expression values before and after primary chemotherapy were 0% (range 0-80) and 30% (range 0-90), respectively (P = 0.03). Our data indicate that primary chemotherapy can modulate tumour cell kinetics and apoptosis-related genes. Pretreatment proliferative activity correlated with tumour response, whilst post-treatment [3H]-dT-LI correlated with relapse free survival.

A region on the long arm of chromosome 16 is frequently deleted in metastatic node-negative breast cancer

The aim of the present study was to define which region of chromosome 16q is most relevant for evaluation of the risk of metastatic recurrence in human breast cancer cases that are lymph node-negative at the time of diagnosis. For this purpose we examined 36 cases of sporadic breast carcinoma subdivided into 3 groups: the first group: no metastatic progression after an average follow-up time of 15 years; including patients with and without lymph node metastases at the time of diagnosis; the second group: N+ (node-positive) patients only, developed metastasis in five years from surgical excision. The last group was composed of patients who developed metastasis but were N0 (node-negative) at diagnosis. A statistically significant association was found between LOH (loss of heterozygosity) at 16q and metastatic progression of the neoplastic disease. 16q LOH was identified as a new independent molecular marker of progression for tumor N0 at diagnosis.

Genetic analysis of lung tumours of non-smoking subjects: p53 gene mutations are constantly associated with loss of heterozygosity at the FHIT locus

Lung cancer is strictly associated with tobacco smoking. Tumours developed in non-smoking subjects account for less than 10% of all lung cancers and show peculiar histopathological features, being prevalently adenocarcinomas. A number of genetic data suggest that their biological behaviour may be different from that of lung tumours caused by smoking, however the number of cases investigated to date is too low to draw definitive conclusions. We have examined the status of p53 and K-ras genes and the presence of loss of heterozygosity (LOH) at the FHIT locus in a series of 35 lung adenocarcinomas that developed in subjects who had never smoked. Results were compared with those obtained in a series of 35 lung adenocarcinomas from heavy-smoking subjects. In the group of non-smoking subjects p53 mutations and LOH at the FHIT locus were present in seven (20%) cases, and the two alterations were constantly associated (P < 0.0001), whereas they were not related in the series of carcinomas caused by smoking. In tumours developed in heavy-smoking subjects, the frequency of LOH at the FHIT locus was significantly higher (P = 0.006) than in tumours from non-smoking subjects. The frequency of p53 mutations in adenocarcinomas caused by smoking was not different from that seen in non-smoking subjects. However, in the group of smoking subjects we observed mostly G:C --> T:A transversions, whereas frameshift mutations and G:C --> A:T transitions were more frequently found in tumours from non-smoking subjects. No point mutations of the K-ras gene at codon 12 were seen in subjects who had never smoked, whereas they were present (mostly G:C --> T:A transversions) in 34% of tumours caused by smoking (P = 0.002). Our data suggest that lung adenocarcinomas developed in subjects who had never smoked represent a distinct biological entity involving a co-alteration of the p53 gene and the FHIT locus in 20% of cases.

Multidrug resistance related genes and p53 expression in human non small cell lung cancer

BACKGROUND

Many genes (mdr1, mrp, DNA topoisomerases II) are known to be involved in the resistance to unrelated drugs (the MDR phenomenon), but the mechanisms of their activation have to be further investigated.

MATERIALS AND METHODS

Because several authors showed that p53 mutated gene was able to induce mdr1 overexpression, we evaluated in 51 non small cell lung cancer samples, already tested for p53 mutations, the expression of mdr1, mrp, DNA topoisomerase II alpha and beta mRNAs by qualitative RT-PCR assays.

RESULTS

Mutations of p53 were found in 56% of cases. Mdr1 expression was detected in 27%, mrp in 100%, topoisomerase alpha in 82% and beta in 94% of the samples.

CONCLUSIONS

It was not possible to detect any relationship between the expression of the MDR-related genes and tumor histological type, stage or lymph node involvement. Nevertheless, a close association between p53 alterations and either mdr1 gene (p = 0.001) or DNA topoisomerase II alpha (p = 0.003) expression was found.

Bcl2 and p53 regulate vascular endothelial growth factor (VEGF)-mediated angiogenesis in non-small cell lung carcinoma

The aim of this study was to investigate the expression of p53 and bcl2 proteins in a series of 107 non-small cell lung cancers (NSCLC), and to relate such protein expression to neovascularisation and the expression of vascular endothelial growth factor (VEGF). Moreover, we analysed the prognostic impact of these biological parameters on overall survival, both in univariate and multivariate analyses. An inverse association was found between bcl2 expression and microvessel count (MVC; P = 0.0004) and bcl2 and VEGF (P = 0.007). In contrast, a significant association was found between p53 expression and MVC (P = 0.03) and p53 and VEGF expression (P = 0.04). In univariate analysis, nodal status (P < 0.000001), MVC (P < 0.000001), bcl2 (P = 0.002), p53 (P = 0.03) and VEGF expression (P < 0.000001) significantly affected overall survival, but in multivariate analysis only MVC and VEGF expression retained their prognostic influence. Our results suggest that bcl2 and p53 possibly control the development of tumour angiogenesis in NSCLC, with putative mediation by VEGF. Moreover, the important influence of angiogenesis in the progression of NSCLC is further highlighted.

Evaluation of FHIT gene alterations in ovarian cancer

The FHIT gene, recently cloned and mapped on chromosome 3p14.2, has frequently been found to be abnormal in several established cancer cell lines and primary tumours. As alterations of chromosome 3p are common events in ovarian cancers with breakpoint sites at 3p14.2, we decided to investigate the role of FHIT in human ovarian tumorigenesis. Fifty-four primary ovarian carcinomas were studied by reverse transcription of FHIT mRNA followed by polymerase chain reaction (PCR) amplification and sequencing of products. The same tumours and matched normal tissues were also investigated for loss of heterozygosity using three microsatellite markers located inside the gene. We found an abnormal transcript of the FHIT gene in two cases (4%) and allelic losses in eight cases (15%). Twelve (22%) of the 54 tumours investigated belonged to young patients with a family history of breast/ovarian cancer. In none of these cases was the FHITgene found to be altered. Our results indicate that FHITplays a role in a small proportion of ovarian carcinomas.

Determination of angiogenesis in human neoplasms: current prognostic and therapeutic implications

The growth of solid tumours beyond a certain mass is strictly dependent on the formation of a vascular bed from a pre-existing host vasculature. This process has been termed OangiogenesisO and its importance in the process of tumour growth and metastasis has recently gained wide acceptance. Studies have been reported in several kinds of human cancers in which the number of microvessels in the most intense areas of neo-vascularisation (Ohot spotsO) have been shown to be strictly related to the development and progression of the tumour. In the majority of these studies highly vascularised tumours showed a poor prognosis and the influence of tumour angiogenesis proved to be independent of conventional prognostic indicators. The evaluation of tumour angiogenesis by quantitative pathology may represent an important prognostic indicator in human cancers and will be increasingly important in the investigation of new therapies directed to inhibiting angiogenesis or targeting tumour vasculature. This review will briefly summarise the current knowledge on the prognostic impact of tumour angiogenesis in human cancers with a final reference to angiogenesis inhibitors which are currently used in phase I/II and III clinical trials.

Spectrum of GCDFP-15 expression in human fetal and adult normal tissues

GCDFP-15, a glycoprotein identified in the cyst fluid of cystic breast disease, is considered to be a marker of apocrine differentiation. Studies on GCDFP-15 localization in adult normal tissues are lacking, and no information on GCDFP-15 expression during fetal development has been reported. We investigated GCDFP-15 expression in a large series of formalin-fixed, paraffin-embedded normal human adult and fetal tissues using the monoclonal antibody BRST-2. In normal adult tissues GCDFP-15 expression was found in all apocrine, lacrimal, ceruminous and Moll's glands and in numerous serous cells of the submandibular, sublingual and minor salivary glands. The serous cells of nasal and bronchial glands were also positive; parotid and laryngeal glands showed rare immunoreactive cells. GCDFP-15-positive cells were observed in all cutaneous eccrine glands from different body sites. In fetal tissues immunoreactivity was observed in numerous acinous cells of all tracheal, bronchial and submandibular salivary glands. GCDFP-15 positivity was identified in numerous cells of all axillary sweat glands and in rare cells of some sweat glands of the thorax, abdomen, back, leg and arm. In both apocrine and nonapocrine glands GCDFP-15 was always localized in the secretory component. These data suggest that GCDFP-15 is a glandular differentiation marker associated with apocrine secretion; that it is expressed in glands that have phylogenetic origins in common with apocrine glands (submandibular salivary and submucosal bronchial glands); and that eccrine cutaneous glands express GCDFP-15 and thus might be referred to as mixed apocrine-eccrine glands. GCDFP-15 is expressed during fetal development and may represent a common marker of embryologically linked glandular structures.

Genetic instability, p53 and nm23 mutation and clinicopathological features in rectal carcinoma

Defective DNA mismatch repair proteins fail to correct replication errors (RERs). These defects may lead to secondary, mutation of oncogenes and tumor suppressor genes. Microsatellite instability might be a marker of such replication errors. Eighteen rectal tumors were examined to evaluate genetic instability, in sporadic rectal cancer by PCR. RERs were observed in 27.8% of the cases. No significant difference was noticed between RER+ and RER- patients as far as prognosis, clinicopathological features and p53 gene mutation are concerned. The incidence of nm23 gene mutation was the only statistically significant difference between the 2 groups. Three patients with only one altered microsatellite showed advanced tumor and nm23 gene mutation. Two cases with 5 altered microsatellites and nm23 gene mutated are disease-free: in one of them the p53 gene was also mutated. Probably more than one altered microsatellite is necessary to protect from the effects of secondary mutations.

FHIT and p53 gene abnormalities in bronchioloalveolar carcinomas. Correlations with clinicopathological data and K-ras mutations

Bronchioloalveolar carcinoma (BAC) is a particular type of adenocarcinoma of the lung which accounts for up to 9 per cent of pulmonary malignancies. The aetiology and pathogenesis of this unique neoplastic disease are still unclear. Three histological subtypes of BAC have been recognized: mucinous, non-mucinous, and sclerosing. Of these, mucinous and sclerosing BAC have a worse prognosis than non-mucinous tumours. The different morphological patterns and clinical outcomes of the subtypes of BAC suggest differences in their biological behaviour. Previous reports have shown that the mucinous form of BAC is characterized by constant mutations at codon 12 of the K-ras gene, whereas the other two histotypes show a frequency of K-ras mutations which is not different from that observed in conventional lung adenocarcinomas. The present study of a series of 51 BACs, previously investigated for K-ras gene mutations, has evaluated the status of two other genes, p53 and FHIT, known to be frequently altered in non-small cell lung cancer. Loss of heterozygosity at microsatellite-containing loci located within the FHIT gene was observed in 22 (43 per cent) BACs. The distribution of FHIT gene abnormalities was not statistically different in the three histological subtypes. p53 mutations were present in 13 (32 per cent) non-mucinous/sclerosing BACs, while no mutations were seen in mucinous tumours (P = 0.039). Correlations with clinicopathological parameters showed that p53 mutations in BACs are associated with more aggressive tumours. No correlations were observed between FHIT or K-ras gene abnormalities and clinicopathological data. In conclusion, these results indicate that FHIT alterations are frequently involved in BAC tumourigenesis and that genetic changes in the p53 and K-ras genes can distinguish between different histotypes of BAC.

Stromal IGF-II messenger RNA in breast cancer: relationship with progesterone receptor expressed by malignant epithelial cells

In breast cancer, insulin-like growth factor II (IGF-II) is stromal in origin and is considered an important regulator of tumour epithelium growth. The presence of progesterone receptor (PR) is expression of an intact oestrogen regulatory pathway of breast malignant epithelial cells and represents a parameter of cell differentiation in breast cancer. In this study we have examined the relationship between IGF-II mRNA expression and ER, PR content in 75 breast cancer. Formalin-fixed paraffin-embedded tissue sections were used to preserve histological details. IGF-II mRNA was evaluated by in situ hybridisation method and ER, PR by immunohistochemistry. IGF-II mRNA was scored semi-quantitatively: 2.6% breast tumour specimen expressed no IGF-II mRNA, 46.7% had low levels of expression (IGF-II-) and 50.7% had moderate or high IGF-II mRNA content (IGF-II+). IGF-II mRNA was found in the stroma fibroblasts surrounding malignant lesions and no signal was detected in malignant epithelial cells. In contrast, ER and PR were expressed only by neoplastic epithelial cells and no immunoreactivity was found in the stroma: 50/75 (66.6%) breast cancer specimens were positive for ER (ER+) and 35 (46.6%) for PR (PR+). Both, IGF-II mRNA and PR were directly correlated with the stromal proliferation (p < 0.05 and p < 0.001, respectively). No relationship was found between IGF-II RNA and ER. In contrast 24/35 (73.5%) PR breast cancer tissues were IGF-II+ (p < 0.01) and a strong correlation was found between epithelial PR immunostaining and stromal IGF-II mRNA content (p < 0.003). Our data indicate that in breast cancer IGF-II mRNA is generally expressed by stromal cells and ER and PR by epithelial cancer cells, and that IGF-II mRNA expression is strongly related with both percentage and staining intensity of PR+ epithelial cancer cells. These data support the hypothesis that IGF-II produced by the fibroblasts may exert a paracrin effect on malignant epithelium regulating its differentiation.

Cyclin D1 and retinoblastoma susceptibility gene alterations in non-small cell lung cancer

Among the major regulators of the G1 restriction point are cyclin D1 and the retinoblastoma gene product (RB). In non-small cell lung cancer (NSCLC), the cyclin D1 gene is amplified/over-expressed in almost 50% of cases, and RB is inactivated in 6-32% of cases. It is of interest to evaluate concurrently the alterations of both genes on the same series of NSCLCs, to investigate whether cyclin D1 and RB alterations are alternative pathways leading to inactivation of the G1 restriction point or if they can occur in the same tumor, possibly exerting an additive effect on cancer progression. We investigated a series of 57 NSCLCs, analyzing cyclin D1 and RB at the gene and protein levels by Southern blot, Northern blot and immunohistochemistry. The cyclin D1 gene was amplified in 18 cases, cyclin D1 immunoreactivity was seen in 25 tumors. Amplification and expression were significantly associated. RB immunohistochemical expression was absent in 9 of 42 informative cases. RB mRNA expression was low to absent in 9 of 45 informative cases, cyclin D1 amplification was associated with normal RB mRNA, and cyclin D1 over-expression was associated with normal RB immunoreactivity, supporting the hypothesis that alterations of cyclin D1 and RB are alternative mechanisms by which tumor cells may escape the G1 restriction point. A concurrent alteration of RB and cyclin D1 was seen in a small subset of NSCLCs. Abnormalities of cyclin D1 and/or RB at the gene and/or expression level were present in more than 90% of cases, stressing that cyclin D1 and/or RB alterations represent an important step in lung tumorigenesis.

Evaluation of epidermal growth factor-related growth factors and receptors and of neoangiogenesis in completely resected stage I-IIIA non-small-cell lung cancer: amphiregulin and microvessel count are independent prognostic indicators of survival

We have determined the expression of transforming growth factor alpha (TGF alpha), amphiregulin (AR), CRIPTO, the epidermal growth factor receptor (EGFR), erbB-2, erbB-3, and tumor angiogenesis in a series of 195 patients with stage I-IIIA non-small cell lung cancer (NSCLC) treated with radical surgery to define their usefulness as prognostic indicators of survival. A variable degree of specific staining in cancer cells was observed for the three growth factors and for the three growth factor receptors in the majority of NSCLC patients. A statistically significant association between overexpression of TGF alpha, AR, and CRIPTO was observed. Enhanced expression of AR was significantly correlated with enhanced expression of erbB-2 and advanced T-stage. A direct association was also detected for overexpression of TGF alpha and of erbB-2 or erbB-3, respectively. Sex, tumor size, nodal status, stage, microvessel count, as a measure of neovascularization, and AR overexpression significantly correlated with overall survival at univariate analysis. In a Cox multivariate analysis, the only characteristics with an independent prognostic effect on OAS were microvessel count [relative hazard (RH), 6.61; P < 0.00001), nodal status (RH, 1.59; P = 0.0013), and AR overexpression (RH, 1.72; P = 0.02). These results suggest that evaluation of neoangiogenesis and of certain growth factors, such as AR, can be useful in addition to conventional pathological staging to select high-risk NSCLC patients who may benefit from post-surgical systemic therapies.

Down-regulation of the nm23.h1 gene inhibits cell proliferation

nm23 gene expression is strictly related to the state of cell growth. The level of its expression parallels the fraction of thymidine-incorporating cells (S-phase cells) in neoplastic mammary tissues and in the synchronously cycling fraction of MCF 1OA cells. nm23.h1 reaches a peak of expression in the S-phase, and is present at very low level during the GO/G1 phase. Two strategies are used to demonstrate the direct involvement of the nm23.h1 gene in the process of cell proliferation. The first consists of transient inhibition of nm23.h1 expression by using anti-sense oligonucleotide treatment; weak inhibitory effect on cell proliferation is observed. The second strategy involves the stable inhibition of nm23.h1 expression by transfection of MCF1OA cells with a plasmid vector expressing the human nm23.h1 anti-sense mRNA. The anti-sense-transfected cells show consistently slower proliferative activity than the control.

Tumor angiogenesis and biologic markers in resected stage I NSCLC

OBJECTIVE

Microvessel count (MC), as a measure of tumor angiogenesis, has been shown to be significantly correlated with metastatic disease in cutaneous, mammary, prostatic, head and neck cancer. We have previously assessed the role of intensity of angiogenesis as predictor of metastasis in surgically resected T1N0M0 NSCLC. We needed to confirm its value, in a prospective larger study on Stage I NSCLC, before its utilization as a prognostic tool for further clinical investigations.

METHODS

In the present report we prospectively investigated 227 patients (206 males, 21 females; median age 65 years) with Stage I NSCLC treated only by radical surgery between March 1991 and December 1994 with utmost care for some biological characteristics (proliferative activity, the blood vessel invasion, angiogenesis and the p53 protein expression).

RESULTS

The operative procedures consisted of 62 pneumonectomies, 148 lobectomies and 17 segmentectomies or wedge resections. With a median follow-up of 36 months (range 15-60), eighty patients have already experienced a local (n = 22) or systemic (n = 58) relapse. Univariate analysis revealed that T factor (T1 versus T2)(P = 0.008) and angiogenesis count (< or = versus > median, 17) (P = 0.0006) were significant predictors of survival. The same variables were also significant predictors of long Disease Free Survival (P = 0.006 and P = 0.004, respectively). On multivariate analysis, however, only the microvessel count retained its level of prognostic significance as regards both overall (P < 0.01) and disease-free survival (P < 0.01).

CONCLUSIONS

The present study corroborates the role of angiogenesis in the metastatic spread of NSCLC and emphasizes its value in the identification of patients in whom surgery should be supplemented by systemic treatment.

Apocrine epithelium of the breast: does it result from metaplasia?

Benign and malignant breast lesions may show an apocrine epithelium considered to be the result of metaplasia. In an attempt to clarify the histogenesis of the breast apocrine epithelium we searched for the presence of apocrine cells or cells with apocrine differentiation during human breast development. We analysed 10 autopsy specimens of female breasts from fetuses between 28 and 40 weeks of gestational age and tissue from 6 normal breasts, obtained after breast reduction in nulliparous young women between 22 and 28 years of age. Formalin-fixed, paraffin-embedded sections were stained with haematoxylin-eosin, PAS-diastase and a monoclonal antibody (BRST-2) anti-GCDFP-15, which is a specific apocrine marker. A 40-week fetal breast was analysed by electron microscopy. No cells with histological and ultrastructural apocrine features were found in the ducts of fetal breasts. All fetal breasts showed some ducts with sparse GCDFP-15-immunoreactive cells; the number of these cells increased with gestational age. PAS-diastase was negative. No cells with apocrine morphology were found in ducts and lobules of normal adult breasts. Scattered GCDFP-15-positive luminal epithelial cells and rare PAS-diastase-positive cells were observed in some lobules of all adult breasts. Cells with biochemical characteristics (GCDFP-15 expression) of apocrine differentiation are evident during human fetal breast development and persist in adult mammary glands. Unknown stimuli may induce these cells to take on an apocrine morphology. Apocrine epithelium of the breast may be a normal process of differentiation rather than metaplasia. We suggest the term "apocrine differentiation precursor cells" for GCDFP-15-positive breast epithelial cells with no apocrine morphology.

Enriched SSCP: a highly sensitive method for the detection of unknown mutations. Application to the molecular diagnosis of lung cancer in sputum samples

Detection of gene mutations by sensitive polymerase chain reaction (PCR)-based methods can allow to identify occult neoplastic cells in a great excess of nonmalignant cells. These molecular approaches have an enormous potential in terms of early diagnosis, detection of occult micrometastases of solid tumors, and minimal residual disease in patients with hematopoietic malignancies. Currently, the applications of such methods are limited, mainly because the high sensitivity required for the identification of rare mutated alleles can be achieved only in cases in which mutations occur in few specific codons of a gene or when the mutation is already known. No methods are available by which few alleles with unknown mutations in tumor genes can be recognized in a great excess of wild-type alleles. We have developed an extremely sensitive method, termed enriched single-strand conformational polymorphism (E-SSCP), which permits detection of a rare alleles with unknown mutations. The method is based on the observation that after a conventional SSCP analysis the vast majority of mutated bands migrate close to the wild-type bands. The area of the gel having the highest chance to hold mutated alleles is physically isolated and is used as substrate for a second round of SSCP. Serially diluted DNA samples containing gene mutations demonstrated detection of 1 mutant/10(6) normal alleles. The E-SSCP assay was first applied to six sputum samples of patients affected by lung cancers with known p53 mutations showing in sputa the same mutations observed in tumors. The technique was then applied to eight cytologically negative sputum samples obtained from patients who later developed a clinically manifested lung carcinoma. In three cases, harboring a p53 mutation in tumor tissue, the E-SSCP analysis allowed the detection of the mutations in sputa months before clinical diagnosis. In conclusion, we have presented a general, highly sensitive technique for the detection of unknown mutations that may have several potential applications and may hold considerable promise for the early detection and study of cancer.

Mortality, severe respiratory distress syndrome, and chronic lung disease of the newborn are reduced more after prophylactic than after therapeutic administration of the surfactant Curosurf

OBJECTIVE

To test the hypothesis that prophylactic treatment with the surfactant Curosurf (Chiesi Farmaceutici SPA, Parma, Italy) improves survival and respiratory problems more than rescue treatment.

DESIGN

Meta-analysis of three prophylaxis versus rescue treatment trials, conducted in four countries.

METHODS

A meta-analysis was performed with the original, individual data of mortality, severe respiratory distress syndrome, and chronic lung disease of 671 newborns as outcomes. The random-effects logistic model (accounting for the trial-within-country structure) was applied and adjusted for imbalances in covariates.

RESULTS

The probability of each outcome differed between the countries, but the actual treatment effect itself did not. The adjusted odds ratios (ORs) and confidence intervals (CIs) for prophylaxis versus rescue were as follows: mortality: OR, .47; 95% CI, .30 to .73; severe RDS: OR, .50; 95% CI, .33 to .74; and chronic lung disease of the newborn in the survivors at day 28 after birth: OR, .54; 95% CI, .34 to .86. Gender, birth weight, gestational age, and prenatal administration of glucocorticosteroids were significant confounding covariates.

CONCLUSION

The analysis shows that for the porcine surfactant Curosurf, prophylactic administration of surfactant has significant advantages over rescue therapy.

Angiogenesis as a prognostic indicator of survival in non-small-cell lung carcinoma: a prospective study

BACKGROUND

Tumors acquire nutrients that are essential for continued growth and an avenue for dissemination to the rest of the body by inducing angiogenesis (i.e., the formation of new blood vessels). Preliminary studies involving a number of different kinds of cancer have indicated that an assessment of tumor angiogenesis may be useful in predicting disease outcome.

PURPOSE

In a prospective study, we evaluated the relationship between tumor angiogenesis and survival for 407 patients with non-small-cell lung carcinoma who were treated with potentially curative surgery.

METHODS

The study population consisted of 360 male and 47 female patients who underwent surgery consecutively at the Department of Surgery, University of Pisa, Italy, from March 1991 through December 1994. Follow-up lasted through February 1996, with a median follow-up for living patients of 29 months (range, 15-60 months). An anti-CD34 monoclonal antibody, which is specific for endothelial cells, and standard immunohistochemical techniques were used to measure angiogenesis in tumor samples. Angiogenesis was quantified in terms of microvessel counts; the counts for single, high-power microscopic fields (magnification x250) in the three most intense areas of blood vessel growth for each sample were averaged. The median microvessel count in this series was 20, and the counts were categorized as follows: 1) low versus high (< or =20 versus >20 microvessels) or 2) in five categories (1-10, 11-20, 21-30, 31-40, and > or =41 microvessels). Disease-free and overall survival during follow-up were assessed. Kaplan-Meier survival curves were modeled in a univariate analysis of patient and tumor characteristics; the Cox proportional hazards model was used in multivariate analysis. Reported P values are two-sided.

RESULTS AND CONCLUSIONS

In the univariate analysis, patients with larger tumors (P for trend <.00001), a more advanced tumor stage (P for trend <.00001), a greater degree of regional lymph node involvement (P for trend <.00001), or more vascularized tumors (high versus low microvessel count, P<.00001) experienced significantly reduced overall survival. When microvessel counts were analyzed in five categories, a highly significant trend (P<.00001) toward worse prognosis was observed with increasing tumor vascularity. In multivariate analysis, tumor microvessel count (P<.00001), tumor size (P = .0006), and regional lymph node status (P<.00001) retained independent prognostic value with respect to overall survival; among these variables, tumor microvessel count, considered as a continuous variable, was the most important, with a relative hazard of death of 8.38 (95% confidence interval = 4.19-16.78) associated with the highest microvessel counts.

IMPLICATIONS

An evaluation of tumor angiogenesis may be useful in the postsurgical staging of patients with non-small-cell lung carcinoma and in identifying subsets of patients who may benefit from different postsurgical treatments.

Vascular endothelial growth factor is associated with neovascularization and influences progression of non-small cell lung carcinoma

Vascular endothelial growth factor (VEGF) plays a pivotal role in the development of neovascularization in both physiological and pathological processes, e.g., developmental and reproductive angiogenesis, proliferative retinopathies, and cancers. Several solid tumors produce ample amounts of VEGF, which stimulates proliferation and migration of endothelial cells, thereby inducing neovascularization by a paracrine mechanism. Recently, VEGF expression has been shown to significantly affect the prognosis of different kinds of human cancer. Because neoangiogenesis represents an important prognostic indicator of poor prognosis in non-small cell lung cancer (NSCLC), we investigated the influence of VEGF during progression of this type of cancer and its relationship to tumoral neovascularization. VEGF expression was significantly associated with new vessel formation (r = 0.44; P < 0.0001). Moreover, in univariate analysis, VEGF expression significantly affected overall and disease-free survival (P = 0.00003 and P = 0. 0004, respectively). Backward stepwise regression analysis indicated that VEGF expression was an independent prognostic factor in patients with NSCLC. These findings support the hypothesis that VEGF is an important angiogenic factor in primary NSCLC and may help in predicting the outcome of this group of cancers.

The spectrum of 67-kD laminin receptor expression in breast carcinoma progression

Laminin is a glycoprotein of the basement membrane (BM), involved in a variety of normal and pathological cellular events including tumour invasion and metastasis. Cells bind laminin through different types of receptor. The 67-kD laminin receptor (67LR) is a cell-surface protein which binds laminin with high affinity. 67LR expression has been shown to increase in neoplastic cells, compared with normal tissues, and 67LR seems to play an important role during the first steps of neoplastic progression. In this study, 67LR expression was analysed during the morphological phases of breast cancer progression from normal tissue to invasive carcinoma. A total of 506 formalin-fixed, paraffin-embedded normal breast structures and lesions were stained by immunohistochemistry usign the MLuC5 monoclonal antibody, which is specific for 67LR. The results show that in normal breast and in any kind of breast lesion, myoepithelial and endothelial cells express 67LR. While 67LR is not seen in the epithelium of normal breast, cysts, adenosis, and benign tumours, it is expressed in the epithelial cells of several hyperplasias and carcinomas in situ, both ductal and lobular, as well as in all invasive carcinomas. The 67LR-positive cell subpopulation expands from hyperplastic lesions to invasive carcinoma, suggesting that 67LR could be related to the induction and progression of breast cancer.

Cyclin-D1-gene amplification and expression in breast carcinoma: relation with clinicopathologic characteristics and with retinoblastoma gene product, p53 and p21WAF1 immunohistochemical expression

Cyclin D1 is a major positive regulator of the G1 restriction point promoting inactivation of the retinoblastoma protein (RB). The cyclin D1 gene is rearranged, amplified and/or over-expressed in several human neoplasms. In the present series of 64 human breast carcinomas, cyclin D1 amplification (4- to 8-fold) was seen in 24% of cases, and cyclin-D1 immunohistochemical over-expression was seen in 50% of cases. Amplification and over-expression were statistically associated; however, divergent result were seen in 30% of cases. Some of these discrepancies may reflect the fact that cyclin-D1 expression may be due to mechanisms other than gene amplification. Cyclin-D1 over-expression, but not cyclin-D1 amplification, was associated with positive oestrogen-receptor immunoreactivity. Cyclin-D1 amplification was associated with high RB expression, and 4 cases (7%) with absent RB immunoreactivity showed no cyclin-D1 amplification nor expression. Our data support the hypothesis that cyclin-D1 amplification may be associated with enhanced gene transcription and with high RB expression, that high ER expression may cooperate in maintaining high levels of cyclin-D1 protein, and that loss of RB function, as assessed by the lack of RB immunoreactivity, may be related to normal cyclin-D1 gene copy number and low cyclin-D1 expression.