Colocalization of human papillomavirus type 11 E1[symbol: see text]E4 and L1 proteins in human foreskin implants grown in athymic mice

The most abundant viral mRNA species in tissues infected with HPV 11 consists of two exons, joining a short segment of open reading frame (ORF) E1 to ORF E4, potentially encoding an protein of 10 kDa. E4 gene products have previously been identified by immunohistochemistry in human tissues infected with HPV 1 and HPV 16, and in HPV 11-infected raft cultures. The E1[symbol: see text]E4 mRNA is produced in abundance in HPV 11-infected human foreskin implants grown in athymic mice. In contrast, the L1 mRNA is present at low levels and appears late in the course of infection. To characterize the relationship of these proteins, polyclonal rabbit antisera were produced against bacterially expressed HPV 11 trpE/E1[symbol: see text]E4 and trpE/L1 fusion proteins and tested in an immunohistochemical assay of paraffin-embedded sections of HPV 11-infected human foreskin tissue fixed with 10% buffered formalin phosphate or zinc formalin. In sections fixed with either fixative, the anti-L1 serum stained nuclei of cells in the upper spinous and granular layers. In contrast, the anti-E1[symbol: see text]E4 serum stained the cell membrane and, to a lesser degree, the cytoplasm of cells in the upper spinous and granular layers of tissue fixed with zinc formalin, but not 10% buffered formalin phosphate. In sections treated with both the E1[symbol: see text]E4 and L1 antisera, cell membrane staining occurred in the same cells that exhibited nuclear staining. The HPV 11 E1[symbol: see text]E4 protein appears to be a cell membrane-associated protein. Expression of the HPV 11 E1[symbol: see text]E4 and L1 proteins may be influenced by similar factors in differentiating cells.

Polyomavirus replicates in differentiating but not in proliferating tubules of adult mouse polycystic kidneys

Previous observations led us to propose that ongoing cellular differentiation, rather then proliferation, may be needed for high-level polyomavirus (Py) replication in permissive organs in vivo. We further tested this proposal by using the C57BL/6J-cpk/cpk mouse model for the autosomal recessive form of polycystic kidney disease (PKD) because both cellular proliferation and differentiation continue into the adult kidney in separate and distinct regions of the kidneys, whereas normal adult kidneys are quiescent and nonpermissive to Py. Adult PKD mice inoculated with Py were assayed for Py DNA replication by in situ hybridization and Southern analysis and for viral gene expression by immunofluorescence 5 days postinfection. The proliferation of collecting duct tubules of PKD kidneys was confirmed by in situ autoradiography for tritiated thymidine incorporation but were observed to be nonpermissive for Py gene expression or replication. Normal differentiated collecting ducts, however, are capable of supporting Py replication in non-PKD runted mice (Rochford et al., 1992). Py DNA, large T-Ag, and VP1, however, were detected in the nonproliferating distal and proximal tubules of the PKD parenchyma. The parenchymal tissues appear to be differentiating in a compensatory response to cyst growth. These results further support the view that in vivo Py replication may require ongoing cellular differentiation rather then mitosis.

Tumor biologic factors and breast cancer prognosis among white, Hispanic, and black women in the United States

BACKGROUND

In the United States, prognosis and survival after the diagnosis of breast cancer is poorer among black patients and, to a lesser extent, among Hispanic patients, compared with white patients. Patients who are black or Hispanic have been reported to present with higher stage or more advanced disease. Even after adjusting for stage, however, survival rates are lower for blacks but not for Hispanics.

PURPOSE

Our purpose was to compare survival, age, tumor size, nodal status, estrogen-receptor (ER) and progesterone-receptor (PgR) status, histologic type, S-phase fraction, DNA ploidy status, HER-2/neu protein expression, and p53 protein status, along with systemic treatment, in a large group of white, black, and Hispanic U.S. women.

METHODS

From 1970 to 1991, breast tumor specimens were submitted to The University of Texas Health Science Center from 31 contributing hospitals throughout the United States for ER and PgR assay. A total of 4885 white, 1016 black, and 777 Hispanic women were eligible for this study. Median follow-up was 57 months.

RESULTS

Overall, white women were significantly more likely to be older and to have smaller tumors, have less lymph node involvement, have tumors with positive ER and PgR status, and have a lower S-phase fraction compared with Hispanic or black women. There were no clinically important differences in DNA ploidy, histologic type, HER-2/neu, and p53 expression among the three groups. Considering all stages, white women had the best overall survival (date of diagnosis to date of death) at 5 years--75% +/- 1% (means +/- SE), with a median survival of 166 months, but Hispanic women had an intermediate survival--70% +/- 2% (median survival, 156 months), and black women had the worst survival--65% +/- 2% (median survival, 117 months) (P < .0001). For node-negative patients, there was no significant difference in disease-free survival (date of diagnosis to date of first recurrence) or overall survival, although blacks tended to have a worse prognosis. For node-positive or locally advanced disease and for metastatic disease, blacks had significantly (P < .0001) worse disease-free and overall survival than did white or Hispanic women. Differences in the use of systemic therapy did not explain these outcomes.

CONCLUSION

A number of biologic factors associated with poor prognosis are found with a significantly increased frequency in breast tumors from Hispanic and, particularly, from black women. Tumors with a more aggressive biology could lead to a higher stage at diagnosis and a poorer survival for the group as a whole.

African Burkitt's lymphoma: a plant, Euphorbia tirucalli, reduces Epstein-Barr virus-specific cellular immunity

Endemicity of Burkitt's lymphoma (BL) coincides with profusion of a plant Euphorbia tirucalli in tropical Africa. E. tirucalli contains 4-deoxyphorbol ester that enhances Epstein-Barr virus (EBV) infection of B lymphocytes. In this study, we found that 4-deoxyphorbol ester reduced EBV-specific cytotoxic T-cell function. Furthermore, the B lymphocytes dually exposed to EBV and 4-deoxyphorbol ester were resistant to EBV-specific T cell cytotoxicity, through down-regulation of latent membrane protein 1 (LMP1), the major target to EBV-specific cytotoxic T-cells. These immunologic findings strengthen the notion that E. tirucalli may be an important environmental risk factor for the genesis of African BL.

Primary splenic large cell anaplastic lymphoma associated with HIV infection

We report a case of primary splenic B-cell CD30 positive large cell anaplastic lymphoma developing in an HIV positive patient. The tumour cells expressed Epstein-Barr virus-associated antigens.

Multivariable analysis of DNA ploidy, p53, and HER-2/neu as prognostic factors in endometrial cancer

BACKGROUND

Several molecular-genetic alterations in endometrial cancers, including aneuploidy and aberrant expression of p53 and HER-2/neu, have been associated with poor prognosis. To determine the importance of molecular-genetic factors relative to more traditional surgical-pathologic prognostic factors, a multivariable analysis was performed.

METHODS

Immunohistochemical staining for p53, HER-2/neu, estrogen receptor, progesterone receptor, and epidermal growth factor receptor was performed on frozen sections from 100 primary endometrial cancers. DNA ploidy was determined using computerized image analysis of Feulgen-stained touch preparations. In addition, information regarding surgical-pathologic features of the cancers was obtained. Univariable analysis was performed followed by multivariable analysis using Cox's proportional hazards model to identify variables predictive of poor prognosis.

RESULTS

With univariable analysis, race, histologic type, stage, grade, myometrial invasion, estrogen receptor, progesterone receptor, ploidy, p53 and HER-2/neu were predictive of the presence of persistent or recurrent disease. In the multivariable analysis, only International Federation of Gynecology and Obstetrics stage (P = 0.005), grade (P = 0.005), myometrial invasion (P = 0.024), and ploidy (P = 0.028) were significant.

CONCLUSIONS

Among molecular-genetic prognostic factors, DNA ploidy was the most strongly predictive of persistent or recurrent disease.

Microvessel density and distribution in ductal carcinoma in situ of the breast

BACKGROUND

Prior studies have suggested that microvessel density is an important prognostic factor in invasive breast cancer. However, the extent and distribution of microvessels in association with ductal carcinoma in situ (DCIS) have not been well defined.

PURPOSE

Our goal was to determine the density and distribution of stromal microvessels in DCIS and to investigate the relationships among microvessel density, histopathologic features, HER2/neu oncogene expression, and tumor proliferation rate.

METHODS

Of 61 consecutive cases of DCIS identified from hospital pathology reports, 55 cases were evaluated. Breast biopsy specimens had been preserved in paraffin blocks for each DCIS case. Histologic sections of formalin-fixed, paraffin-embedded tissue were stained with hematoxylin-eosin and immunostained for factor VIII-related antigen, the HER2/neu oncoprotein, and the proliferative-associated antigen detected by the Ki-S1 antibody. Factor VIII-stained sections from each case were independently examined by two pathologists and overall tumor-associated stromal microvessel density was scored semiquantitatively on a 1+ to 3+ scale by each observer. Quantitative microvessel counts of DCIS-associated stromal microvessel density were performed. The presence or absence of a cuff of microvessels in immediate apposition to the basement membrane of involved spaces was also evaluated.

RESULTS

A variable number of microvessels were found to be present in a diffuse pattern surrounding spaces involved with DCIS. Semiquantitative microvessel scores were 2+ in the majority of cases (53%); 22% of cases were 1+, and 25% were 3+. Quantitative microvessel counts ranged from 17 to 80 vessels per 100x field (0.45 mm2), with a mean +/- SD of 42.9 +/- 16.6. Comedo-type lesions were significantly (P = .004) more often associated with 3+ microvessel density than non-comedo-type lesions by semiquantitative assessment. As determined by both semiquantitative and quantitative analysis, respectively, the presence of prominent microvessel density was significantly associated with marked stromal desmoplasia (P = .05 and P = .04), HER2/neu expression (P = .03 and P = .0002), and high Ki-S1 proliferation index (P = .05 and P = .01). Vascular cuffing around involved spaces was identified in 21 of the 55 cases (38%) and was not significantly associated with histologic features, HER2/neu expression, or Ki-S1 proliferation index.

CONCLUSIONS

DCIS of the breast is characterized by two patterns of stromal microvessels. The first pattern is a diffuse increase in stromal microvessels surrounding involved spaces. This pattern is particularly prominent in comedo-type lesions with marked stromal desmoplasia. The second pattern is microvessel cuffing of involved spaces that is present in only a minority of cases and appears unrelated to histologic features evaluated, including DCIS subtype.

Expression of EGFR, HER-2/neu, P53, and PCNA in endometrioid, serous papillary, and clear cell endometrial adenocarcinomas

Expression of four biologic markers was studied in 69 cases of endometrial cancer to identify their association with cell type, decreased survival, and increased tumor metastasis. Cell types included endometrioid (n = 45), serous papillary (n = 16), and clear cell (n = 8). Immunohistochemical stains were employed to detect the presence of epidermal growth factor receptor (EGFR), HER-2/neu, p53, and proliferating cell nuclear antigen (PCNA). Analysis revealed that EGFR was expressed in 49%, HER-2/neu in 59%, p53 in 9%, and PCNA in 16% of tumor specimens. HER-2/neu overexpression was significantly associated with depth of myometrial invasion. p53 and PCNA immunoreactivity significantly correlated with nonendometrioid histology, although PCNA was less specific in labeling these less favorable cell types. EGFR immunoreactivity also significantly correlated with nonendometrioid cell types and tumor metastases at time of diagnosis. Seventy-seven percent of patients with metastatic disease were EGFR-positive versus 36% positivity in patients with no evidence of metastases (P < 0.002). For patients with endometrioid adenocarcinoma, evidence of EGFR overexpression decreased survival from 89 to 69% (P < 0.04). In the serous papillary and clear cell category, EGFR positivity decreased survival from 86 to 27% (P < 0.03). EGFR strongly correlates with tumor metastasis and patient survival in endometrial cancer. Altered expression of this oncoprotein may serve as a guide to prognosis and treatment in these patients.

Immunohistochemical analysis of estrogen and progesterone receptor and neu expression in breast carcinoma

To elucidate the frequency and biological significance of the expression of estrogen receptor (ER), progesterone receptor (PR), and neu oncogene in breast carcinoma, ER, PR and neu proteins were examined by immunohistochemical assay in 74 Taiwanese patients with breast carcinoma. In total, 56.8% and 48.7% of breast carcinoma were positive for ER and PR, respectively. In 91.9% of cases, the patients were either positive (48.7%) or negative (43.2%) for both ER and PR. Well differentiated carcinoma had higher frequencies of ER- (p < 0.02) and PR-positivities (p < 0.01). The ER and PR status did not correlate with tumor size, stromal lymphoid infiltration or axillary node status. The neu oncoprotein was expressed in 25.7% of breast carcinomas, but did not correlate with ER and PR status, tumor size, tumor grade, lymphoid infiltration, or axillary node status.

Prevalence and significance of HER-2/neu expression in early epithelial ovarian cancer

BACKGROUND

Although expression of the HER-2/neu oncogene may be of some prognostic importance in advanced ovarian cancer, its role in early-stage disease has not been established. The current study examined the prevalence and significance of HER-2/neu expression in early epithelial ovarian cancer.

METHODS

The authors analyzed the expression of HER-2/neu on frozen tumor specimens from 40 patients with early epithelial ovarian cancer using the indirect immunoperoxidase technique with monoclonal antibodies that detect epitopes on the extracellular domain of the HER-2/neu protein. All patients underwent comprehensive surgical staging. HER-2/neu expression was graded as negative, weak, moderate (1+ to 2+), or strong (3+). Complete clinical data and long-term follow up were available for all patients.

RESULTS

The distribution of patients by stage was as follows: Stage IA, 6; IB, 0; IC, 14; IIA, 4; IIB, 6; IIC, 10. The mean patient age was 53 years. Fourteen patients had serous tumors; nine, endometrioid; eight, clear cell; eight, mucinous; and one, undifferentiated. Intratumoral heterogeneity of HER-2/neu expression was observed with most specimens. In eight specimens (20%), some areas of the tumor showed strong (3+) expression, beyond the level that can be seen in normal ovarian epithelium. Twenty-eight specimens (70%) showed moderate (1+ to 2+) staining, whereas four specimens (10%) showed negative or weak staining. At a mean follow-up time among surviving patients of 32 months, 15 patients (37%) have had cancer recurrence. No statistically significant relationship was found between HER-2/neu expression and survival, disease-free survival, stage, or grade. A significant increase was found in 3+ expression of HER-2/neu in clear cell tumors.

CONCLUSION

Consistent HER-2/neu overexpression occurs infrequently in early ovarian cancer, making it unlikely that such overexpression is a general early event in ovarian carcinogenesis. HER-2/neu expression does not appear to be a strong prognostic marker in early epithelial ovarian cancer.

Detection of human papillomavirus L1 protein in condylomata acuminata from various anatomical sites

BACKGROUND AND OBJECTIVES

Though human papillomavirus (HPV) DNA can be detected in the majority of condylomata acuminata, the major capsid protein of HPV (L1 protein) can be detected in only 10% to 50% of lesions in immunohistochemical assays.

GOAL OF STUDY

To evaluate the association between anatomic location of genital HPV infections and the ability to detect HPV L1 protein.

METHODS

Condylomata acuminata from 49 male and 51 female patients were evaluated for L1 protein by immunohistochemistry. Thirty of these lesions were vulvar; 20 were cervical; 1 was vaginal; 45 were penile; and 4 were perianal. A quantitative analysis of L1-positive nuclei in the lesions was performed.

RESULTS

L1 protein was detected in 20 (20%) of all lesions. L1 protein was detected in seven (35%) of the cervical lesions compared to nine (12%) of exophytic condylomata acuminata of males and females (P = 0.038). A statistically significant difference was noted between cervical and exophytic condylomata acuminata lesions (46.6 vs. 7.8) (P = 0.0006). No association between oral contraceptive use and L1 protein detection was found.

CONCLUSIONS

The major capsid protein of HPV can be detected in condylomata acuminata of the uterine cervix more often, and in higher quantities, than in lesions of the vulva or penis. Further studies are needed to assess the effects of sex hormones and the anatomic location of the infection as they relate to transmission of HPV.

Detection of DNA and E7 transcripts of human papillomavirus types 16, 18, 31 and 33, TGF beta and GM-CSF transcripts in cervical cancers and precancers

The association of human papillomavirus (HPV) with a high proportion of cervical cancers should allow the efficiency of cytological screening methods to be improved. We report here that quantitative detection of HPV types 16, 18, 31 and 33 DNA and the corresponding E7 transcripts by polymerase chain reaction (PCR) may be of value in identifying precancers and cancers. In clinical specimens with major cervical lesions, the level of E7 transcription does not appear to be related to concomitant transcription of either transformation growth factor-beta (TGF beta) or granulocyte-macrophage colony stimulating factor (GM-CSF) genes.

Expression of p185erbB2 and p21ras in carcinoma, dysplasia, and intestinal metaplasia of the stomach: an immunohistochemical and in situ hybridization study

The expression of p185erbB2 and p21ras was determined immunohistochemically in normal mucosa, intestinal metaplasia, dysplasia and in intestinal and diffuse type carcinoma of the stomach. The positive rates of p185erbB2 and p21ras in intestinal type were significantly higher than those of diffuse-type carcinoma. The results indicate that there are differences not only in clinical and biologic features, but also in molecular abnormalities between the two types of stomach cancer. Positive staining of cell membrane for p185erbB2 was observed specifically in intestinal type cancer, but not in the other lesions. Positive expression of p185erbB2 on the cell membrane appears to be a useful marker in identification of malignant change of gastric mucosa, as well as a late event of gastrocarcinogenesis. The results of in situ hybridization analysis in cancer tissues were consistent with those obtained by immunohistochemistry and demonstrated amplification of erbB2 gene at the mRNA level. No significant difference of p21ras expression was found among intestinal metaplasia, dysplasia, and intestinal type carcinoma; therefore, it might not be a specific marker of malignancy in gastric mucosa. Expression of p21ras may be an early event in the development of lesions predisposing to carcinoma.

Human herpesvirus 6 infects cervical epithelial cells and transactivates human papillomavirus gene expression

To examine whether human herpesvirus 6 (HHV-6) is capable of infecting human cervical epithelial cells and altering expression of human papillomavirus (HPV) genes, HPV-immortalized or -transformed carcinoma cell lines were infected with HHV-6 variant A. No cytopathic effect was observed in infected cervical cells. However, immunofluorescence indicated that infected cells expressed early-late proteins of HHV-6 by day 3 postinfection. HHV-6 DNA was also detected by Southern blot hybridization after infection and persisted through continued subculture in an episomal state as proven by Gardella gel electrophoresis and fluorescence in situ hybridization. HHV-6 infection enhanced expression of HPV RNAs encoding the viral oncoproteins E6 and E7. Transient transfection assays showed that two HHV-6 molecular clones, pZVB-70 and pZVH-14, upregulated transcription 9- to 15-fold from a receptor plasmid containing the HPV type 18 regulatory sequences which control transcription in vivo. Cervical carcinoma cells infected with HHV-6 induced more rapid development of tumors in mice than did noninfected cells. These results are the first evidence that human cervical epithelial cells can be infected with HHV-6 and that HHV-6 contains transactivators which stimulate the HPV-transforming genes.

Expression of gp185HER-2 in human cutaneous melanoma: implications for experimental immunotherapeutics

Over-expression of the HER-2 oncogene correlates with poor prognosis in breast and ovarian carcinomas. Using a sensitive immunohistochemical assay, we have detected low levels of gp185HER-2 in intradermal nevi (78%) and in primary (75%) and metastatic melanomas (58%). The HER-2 gene product expressed by cultured melanoma cells had the expected molecular weight, but no levels of tyrosine phosphorylation could be detected. Consistently, we were unable to inhibit in vitro growth of melanoma cells with an anti-gp 185HER-2 MAb, in conditions in which the growth of SKBr-3 breast-carcinoma cells was severely impaired. However, immunotoxins to gp 185HER-2 were able to kill gp185HER-2-positive melanoma cells. These data indicate that low levels of gp185HER-2 are expressed by the melanocyte lineage, with no correlation with transformation or tumor progression. Nevertheless, gp185HER-2 appears a suitable target for immunotherapy of cutaneous melanoma.

DNA damage induced p53 mediated transcription is inhibited by human papillomavirus type 18 E6

Cervical cancer is similar to other human cancers in that it develops through a multistep process. However, infection with oncogenic human papillomaviruses (HPVs) is believed to be essential for the initiation of this disease. Although HPV may play a central role in the early stages of neoplasia, the accumulation of mutations in an assortment of genes precedes the development of malignant cervical carcinoma. The mechanisms by which abnormalities accumulate are various, but it is possible that viral proteins are involved. In particular, the viral E6 oncoprotein has been shown to interact with the cellular tumour suppressor protein p53, which is involved in DNA damage repair pathways. Hence, E6 may contribute to the genomic instability through this interaction with p53. We have tested this hypothesis by monitoring the effects of E6 upon DNA damage induced p53 transcriptional activity. This study shows that HPV-18 E6 inhibits p53 transcriptional activity following genotoxic stress with UV radiation. No effect was observed when a mutant E6 unable to direct the degradation of p53 was included in this assay. These results suggest that continued E6 expression may contribute to the accumulation of DNA damage associated with the progression of cervical cancer.

Scanning the structure and antigenicity of HPV-16 E6 and E7 oncoproteins using antipeptide antibodies

The structure and antigenicity of the HPV-16 E6 and E7 oncoproteins was studied using a set of antisera against overlapping synthetic peptides. We report that antigenic, mobile regions of the native proteins, as defined by reactivity with antipeptide antisera, occur at the N-termini of both E6 and E7 proteins, corresponding to regions of known or suspected protein-protein interactions. The putative zinc finger domains were consistently non-reactive, despite computer predictions of relatively high antigenicity, suggesting that the proposed zinc finger regions are held in stable secondary structures that the peptides were not able to mimic. In E6, the linker region between the two zinc fingers was antigenic, indicating that the two zinc finger structures might be able to articulate relative to one another by a flexible linker region. The highly antigenic N-terminal region of HPV-16 E7 was also found to be antigenic in E7 of both HPV-11 and HPV-18, indicating that the E7 proteins of different HPV types have similar antigenic structures. The identification of antigenic regions of the E6 and E7 proteins should be therefore be useful in the design of site-directed antibodies against E6 and E7 for numerous HPV types.

Restoration of telomeres in human papillomavirus-immortalized human anogenital epithelial cells

Loss of telomeres has been hypothesized to be important in cellular senescence and may play a role in carcinogenesis. In this study, we have measured telomere length in association with the immortalization and transformation of human cervical and foreskin epithelial cells by the human papillomavirus type 16 or 18 E6 and E7 open reading frames. By using a telomeric TTAGGG repeat probe, it was shown that the telomeres of precrisis normal and E6-, E7-, and E6/E7-expressing cells gradually shortened with passaging (30 to 100 bp per population doubling). Cells that expressed both E6 and E7 went through a crisis period and gave rise to immortalized lines. In contrast to precrisis cells, E6/E7-immortalized cells generally showed an increase in telomere length as they were passaged in culture, with some later passage lines having telomeres that were similar to or longer than the earliest-passage precrisis cells examined. No consistent association could be made between telomere length and tumorigenicity of cells in nude mice. However, of the three cell lines that grew in vivo, two had long telomeres, thus arguing against the hypothesis that cancer cells favor shortened telomeres. Our results indicate that arrest of telomere shortening may be important in human papillomavirus-associated immortalization and that restoration of telomere length may be advantageous to cells with regard to their ability to proliferate.

Elevated erbB-2 oncoprotein levels in preoperative and follow-up serum samples define an aggressive disease course in patients with breast cancer

BACKGROUND

Recent evidence indicates that a soluble fragment of the erbB-2 oncogene product may be released from cell surface and become detectable in the serum of patients with breast cancer.

METHODS

To study the diagnostic utility of this phenomenon, the authors measured serum erbB-2 levels with a quantitative enzyme-linked immunosorbent assay in 227 preoperative samples from women who underwent breast surgery and in 339 samples from 225 patients with breast cancer during follow-up.

RESULTS

Eleven (9%) of 114 preoperative samples from patients with a histologically verified breast cancer and 2 of 113 (1.8%) from patients with benign breast tumors had elevated (greater than 20 U/ml) serum erbB-2 antigen levels. Ten (91%) of the 11 carcinomas and one of the benign tumors from patients with elevated serum erbB-2 levels also showed overexpression of the erbB-2 protein in immunohistochemical analysis of tissue sections. Elevated preoperative serum erbB-2 levels were predominantly found in patients with large tumors, and those with axillary lymph node or distant metastases. Sixty-three of the 339 (19%) follow-up samples had elevated serum erbB-2 antigen levels. Approximately one-third (30.9%) of the samples taken during recurrent disease were serum erbB-2 positive, which is close to the overall overexpression rate of this oncogene. Elevated erbB-2 levels were more common in patients whose disease was not responsive to treatment. Patients with distant metastases had elevate erbB-2 levels more often (40%) than did those with locoregional recurrence (20%). Elevated erbB-2 levels predicted the appearance of metastases within the next 6 months in 10 of 27 (37%) patients.

CONCLUSION

The study's results suggest that assay serum erbB-2 levels may be valuable in the follow-up and monitoring of patients with breast cancer whose primary tumors show erbB-2 overexpression by immunohistochemistry.

[Oral non-Hodgkin lymphomas and Epstein-Barr virus]

The oropharynx is the site of primary infection and further propagation of the Epstein-Barr virus (EBV). From here, virus is shed to saliva and infects peripheral blood lymphocytes. Eight oral Non-Hodgkin lymphomas (NHL) were investigated for the presence of EBV both by immunohistochemistry for the latent membrane protein (LMP) and a PCR-strategy for general and subtype-specific viral sequences. All but one NHL turned out to be negative both by LMP and PCR. EBV general sequences and of the two viral subtypes A and B were found in an HIV-1+ patient. It is concluded that it is not the localisation which predetermines NHLs to EBV-positivity but merely the underlying disease (this study) or the type of tumour (previous studies).

Increased natural killer cell activity correlates with low or negative expression of the HER-2/neu oncogene in patients with breast cancer

BACKGROUND

Increased expression of the HER-2/neu oncogene in breast cancer correlates with decreased estrogen receptor concentration and seems to be an important prognostic factor. The authors investigated whether there is a correlation between HER-2/neu expression and immunologic parameters representing tumor defense in patients with breast cancer.

METHOD

A Western blot analysis was used to investigate HER-2/neu expression, whereas a chromium-release assay using the K562 cell line as target was used to measure natural killer (NK) cell activity.

RESULTS

In patients with breast cancer, NK cell activity was significantly higher compared with patients with benign tumors (P = 0.006) or healthy control subjects (P = 0.002). Moreover, 23.3% of patients with breast cancer showed an overexpression of HER-2/neu protein. Within this group of patients, NK cell activity was significantly lower (45.6 +/- 16.1%) compared with the group with no HER-2/neu overexpression (57.3 +/- 11.0%). NK cell activity did not increase in patients with HER-2/neu overexpression. Thus, there was a statistically significant correlation of cytolytic effector cell function with HER-2/neu expression of the tumor (P = 0.003), and HER-2/neu overexpression correlated with a negative estrogen receptor status (P = 0.005).

CONCLUSION

These data add further evidence to previous observations from the authors' laboratory that certain tumor characteristics may be associated with reactions of the host with breast cancer.

erbB-2 and myc oncoproteins in sera and tumors of breast cancer patients

This study compares the prevalence of elevated serological levels of erbB-2 and myc proteins in 36 breast cancer patients and 25 healthy, ambulatory female controls. The controls were frequency matched to the cases by age and ethnicity. Oncoprotein levels were determined blind to the "case-control status" of the individual from whom the specimen was derived. Corresponding tissue levels were examined in tumors of the 13 cases from whom sufficient tissue was available. Serum oncoproteins were elevated as follows: erbB-2 in one control (4%) compared with nine cases (25%; PFisher's exact = 0.03); myc in no control (0%) compared with seven cases (19%; PFisher's exact = 0.02). Elevated serum levels of erbB-2 or myc oncoproteins were detected in four of the seven cases (57.1%) of in situ cancer without evidence of infiltration. In all cases with elevated serum oncoproteins where tumor tissue was available, the corresponding protein was elevated in the tumor. The three cases who had elevated preoperative serum oncoprotein levels and from whom it was possible to procure postoperative specimens had normal postoperative serum oncoprotein levels. We conclude that (a) erbB-2 and myc oncoproteins are elevated in a proportion of breast cancer patients, (b) the tumor seems to be the source of the serum elevation, and (c) these proteins may be useful as part of a panel of biomarkers of early malignant disease.

Flow cytometric detection of DNA tumor virus nuclear oncogene products in unfixed cells: saponin FACS of viral oncogene products

Immunofluorescent analysis is a standard method for detecting DNA virus oncoproteins in transformed cells. Here we demonstrate the detection of DNA virus nuclear oncoproteins by flow cytometry of unfixed cells, after saponin permeabilization. This method could to be of value in the evaluation and quantitation of oncogene products in transformed cells.