Inhibition of murine renal carcinoma pulmonary metastases by systemic administration of interferon gamma: mechanism of action and potential for combination with interleukin 4

We have previously demonstrated that IFN-gamma causes cell growth inhibition and up-regulation of MHC antigens in human renal cell carcinoma cell lines. In this study, we have investigated the therapeutic potential of IFN-gamma for the treatment of 5-day established pulmonary metastases induced by i.v. injection of Renca cells, a murine renal adenocarcinoma. We found that systemic injections of IFN-gamma significantly reduced the number of lung metastases in a dose-dependent manner and increased mouse survival. Histological evaluation of IFN-gamma-treated lungs showed residual small tumor nodules containing extensive necrosis and mononuclear infiltrates. Immunohistochemistry studies on lung sections showed macrophage infiltration into tumor nodules, and in vivo depletion of macrophages partially inhibited IFN-gamma antitumor effect, suggesting a role for the macrophages in tumor destruction. Lymphocyte depletion of either natural killer (NK) cells or CD4+ or CD8+ T-cell subsets or both T-cell subsets did not affect the IFN-gamma effect, whereas depletion of both NK and T cells decreased the antitumor activity of IFN-gamma. These data indicate that neither T cells nor NK cells are essential for this activity but that either lymphocyte population can contribute to the IFN-gamma effect. An optimal dose of IFN-gamma inhibited by 60% the growth of Renca cells treated for 3 days in vitro, but this effect was transient and less pronounced in a long-term colony assay, suggesting that IFN-gamma direct growth inhibition may play a role but may not be sufficient to mediate its antitumor effect in vivo. In vitro, IFN-gamma caused up-regulation of class I MHC antigens and induction of class II antigen expression in Renca cells, an effect that may enhance Renca immunogenicity but may be relevant only when a T-cell response is elicited. A sequential administration of IFN-gamma followed by interleukin 4 was therapeutically better than IFN-gamma alone for the treatment of advanced pulmonary metastases, probably due to different antitumor mechanisms induced by these two cytokines.

Interleukin-13 receptors on human prostate carcinoma cell lines represent a novel target for a chimeric protein composed of IL-13 and a mutated form of Pseudomonas exotoxin

We have discovered a new cell surface protein in the form of interleukin-13 receptor on several solid tumor cells, including human renal cell carcinoma cells (Obiri et al., 1995; Debinski et al., 1995). This study reports that human prostate cancer cell lines also express high affinity IL-13 receptors (Kd = 159 pM). These receptors are functional because IL-13 surprisingly increased proliferation of all three prostate cancer cell lines studied as determined by thymidine uptake and clonogenic assays. IL-13 receptors on prostate cancer cell lines were targeted using a chimeric protein composed of IL-13 and a mutated form of Pseudomonas exotoxin (PE38QQR). This molecule, termed IL13-PE38QQR, has been found cytotoxic to all three prostate cancer cell lines as determined by the inhibition of protein synthesis. The IC50 ranged between 1 nmol/l, to 15 nmol/l. These data were confirmed by clonogenic assays in which IL13-PE38QQR almost completely inhibited colony formation at 10 nmol/l. IL13-PE38QQR was not cytotoxic to cells that express little or no IL-13R. Heat inactivated IL13-PE38QQR was not cytotoxic to prostate cancer cells indicating specificity. IL13-PE38QQR was also cytotoxic to colonies when they were allowed to form first for several days before the addition of toxins. Our data suggest that additional studies should be performed to target IL-13 receptor bearing prostate cancer.

Diagnostic and prognostic markers for human prostate cancer

BACKGROUND

The incidence and mortality of prostate cancer are increasing at alarming rates, partially due to an aging population. Early detection of prostate cancer, using clinically sensitive procedures and/or tumor markers (e.g., prostate-specific antigen [PSA]), is of prime importance. However, the choice of therapeutic interventions for prostate cancer at the time of diagnosis is largely dependent on clinical and pathologic staging and prediction of the degree of aggressiveness of the disease. Clinically applicable prognostic markers are urgently needed to assist in the selection of optimal therapy.

METHODS

Literature review of the potential diagnostic and prognostic markers for human prostate cancer.

RESULTS

Well-established tissue prognostic indicators, including histologic grade, margin positivity, pathologic stage, intraglandular tumor extent, and DNA ploidy, are not reviewed in this paper. Recently, a number of novel markers have been identified. In this paper, we begin with a discussion of a number of well-established as well as investigational diagnostic markers and then focus on evaluation of prognostic markers. Diagnostic markers that have prognostic value and investigational prognostic markers are also discussed.

CONCLUSIONS

Currently, only PSA is utilized for early diagnosis and monitoring of prostate cancer. A number of potential prognostic markers warrant further investigation. Multimarker analysis is implicated.

The predictive value of race as a clinical prognostic factor among patients with clinically localized prostate cancer: a multivariate analysis of positive surgical margins

OBJECTIVES

Several investigators have reported that African-American men with clinically localized prostate cancer have poorer survival than do white men. In addition, prostate cancer in African-American men is commonly diagnosed at a more advanced stage of disease. Is race or ethnicity predictive of outcome of clinically localized prostate cancer? It has been reported that the presence of positive surgical margins significantly influences time to progression independently of other prognostic factors. Therefore, we have elected to conduct a multivariate analysis of clinical factors including race as potential predictors of positive surgical margin outcome.

METHODS

We studied 369 consecutive men (120 African-American and 249 white) who had radical prostatectomies at a single institution. Comparisons by race of Gleason score, stage, presence of positive surgical margins, and mean preoperative prostate-specific antigen (PSA) level were carried out.

RESULTS

Our data demonstrate that African-American men have more pathologically locally advanced prostate cancer than do white American men: 69% among blacks compared with 57% among whites. However, the difference in rate of positive surgical margins between blacks and whites is statistically significant: 58% among blacks versus 40% among whites (P = 0.002). Four factors were predictive of positive surgical margins: preoperative PSA level, race, clinical stage, and Gleason score.

CONCLUSIONS

We have demonstrated that race is an independent predictor of positive surgical margins among patients with clinically localized prostate cancer and should be included in treatment decisions. In addition, the risk of positive surgical margins increases noticeably when PSA is greater than 10 ng/mL.

The mechanism of local tumor irradiation combined with interleukin 2 therapy in murine renal carcinoma: histological evaluation of pulmonary metastases

We have demonstrated that tumor irradiation enhanced the therapeutic effect of interleukin 2 (IL-2) on pulmonary metastases from a murine renal adenocarcinoma, Renca. To investigate the mechanism of interaction between tumor irradiation and IL-2 therapy, we have histologically evaluated the effects of each therapy alone or in combination on Renca pulmonary metastases. Following treatment of established lung metastases with irradiation and IL-2 therapy, lung sections were processed for H&E or immunohistochemical staining. We found that tumor irradiation or IL-2 therapy locally induced vascular damage, resulting in multifocal hemorrhages and mononuclear cell mobilization in the lung tissue. This effect was amplified in lungs treated with the combined therapy. Immunohistochemistry showed that irradiation produced a macrophage influx into irradiated tumor nodules, and systemic IL-2 therapy induced T-cell infiltration in tumor nodules. Lungs treated with the combined therapy exhibited massive macrophage, T-cell, and natural killer cell mobilization in disintegrating tumor nodules and in the lung tissue. This combined therapy caused a decrease in the number of proliferating tumor cells and an increase in the number of apoptotic cells, which were more marked than with either therapy alone. We suggest that the macrophages mobilized by radiation-induced tissue injury could play a role in phagocytosis of apoptotic tumor cells, processing and presenting of tumor antigens for a systemic immune response activated by IL-2. Tumor destruction may result from the concomitant action of activated T cells, natural killer cells, and macrophages infiltrating the tumor nodules.

A comparison of the W-stapled ileal reservoir with hand-sewn reservoirs for orthotopic bladder replacement

OBJECTIVES

Confidence has increased in the use of an orthotopic reservoir to the urethra after a cystoprostatectomy for bladder cancer; however, many surgeons would welcome a method to simplify the operative procedure. The availability of absorbable staples on a GIA stapler allows study of the incorporation of stapling procedures into formation of a reservoir. Because of the success of hand-sewn W-configured ileal reservoirs, we initiated a Phase II study to evaluate absorbable staples in formation of a W-configured reservoir. We now present an expanded contemporary series comparing a W-stapled ileal neobladder with hand-sewn ileal (Studer) or hand-sewn ileocolic (Le Bag) reservoirs.

METHODS

Forty-five selected patients underwent orthotopic urinary diversion after cystoprostatectomy for bladder cancer (n = 42) or prostate cancer (n = 3) using one of the three methods of reservoir construction. There were 43 men and 2 women. The evaluation included a urodynamic evaluation and a questionnaire sent to patients inquiring about urinary function.

RESULTS

Most patients did well with the W-stapled ileal reservoir but 6 of 19 evaluable patients had unsatisfactory reservoir characteristics. Three patients needed an augmentation cystoplasty and 3 had higher pressure, smaller volume reservoirs. Reservoir function appeared to be consistently more favorable in patients with either of the hand-sewn reservoirs using an ileal or ileocolic segment.

CONCLUSIONS

Although the W-stapled ileal reservoir is safe and allows reservoir formation quickly, the inconsistencies of the results discourage its use in the particular configuration described. Failure of the reservoir to distend could be a function of reservoir design, areas of ischemia in the reservoir, or reaction to staple material. Absorbable staples on the GIA instrument may work satisfactorily for formation of an ileocolic reservoir for continent cutaneous diversion. However, the W-configured orthotopic reservoir as constructed using absorbable staples in this study is inferior to a hand-sewn ileal or ileocolic neobladder.

High levels of tissue inhibitor of metalloproteinase-2 (TIMP-2) expression are associated with poor outcome in invasive bladder cancer

The matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) have been associated with tumor invasion and metastasis in many human cancers. Immunohistochemical studies were performed on frozen tumor samples from 42 patients with invasive bladder cancer treated by cystectomy with monoclonal antibodies against the Mr 72,000 gelatinase A (MMP-2), Mr 92,000 gelatinase B (MMP-9), and TIMP-2 to evaluate their significance in bladder cancer. Immunoreactivity for the gelatinases was predominantly tumor cell-associated, whereas strong TIMP-2 staining was mostly detected in the stroma. Tumor cells demonstrated moderate to strong reactivity for MMP-2 and MMP-9 in 71 and 71% of cases, respectively, which did not correlate with stage, grade, or outcome. Tumor cells were positive for TIMP-2 in 26 (62%) of 42 cases, and this correlated with a worse outcome (69 versus 25% died of disease; P < 0.05). In 31 (74%) of 42, there was moderate to strong stromal staining for TIMP-2; this also was associated with a poor outcome (65 versus 25% died of cancer; P < 0.05). Tumor basement membrane (BM) status was investigated using an antibody to type IV collagen. In 9 cases, the invasive tumor nests were surrounded by an intact BM; in 7 of these, stromal staining for TIMP-2 was absent. None of these 9 patients (0%) died of tumors compared with 7 (100%) of 7 with complete loss of BM staining (P < 0.001). These results suggest a potential role for TIMP-2 and BM staining as prognostic indicators in invasive bladder cancer.

Issues on early diagnosis and treatment of localized prostate cancer

Controversies abound in relation to the treatment of every stage of prostate cancer and its natural history. We critically evaluate the controversies and information that exist. An ongoing autopsy project at Wayne State University aims to: define the prevalence of incidental cancer in subjects between 20 and 70 years of age; study the potential difference between Caucasians and Blacks; and to analyze other associated histological lesions such as prostatic intraepithelial neoplasia (PIN) and atypical adenomatous hyperplasia. Initial results note that there was only a weak correlation between high-grade PIN and incidental carcinoma, both lesions started to present at an early age with a progressive increase after the seventh decade, and there was no racial difference observed among Caucasians and African-American males. These results pose several questions which need further explanation. Most studies use digitorectal examination, transrectal 7-MHz ultrasonography and prostate-specific antigen for the early diagnosis of prostate cancer, we attempt to determine the best and most economical combination presently available. In discussing the therapeutic options for patients with localized prostate cancer, we review our personal experience with surgery and radiotherapy.

Age and racial distribution of prostatic intraepithelial neoplasia

AIMS

To study the prevalence, extent and evolution of high-grade prostatic intraepithelial neoplasia (HGPIN) in African-American and Caucasian men of a wide age range in order to help clarify the role this lesion may play in the racial differences of prostate cancer.

METHODS

The lesion was documented in step-sectioned, entirely submitted prostates of two study populations: 525 autopsied men who died of trauma and 1,000 patients who had retropubic radical prostatectomy for clinically localized carcinoma of the prostate.

RESULTS

We found that HGPIN starts in young individuals and increases progressively with advancing age in both races but is more prevalent in African-Americans. Additionally, the more extensive form of HGPIN with multifocal or diffuse involvement of the gland appears at a younger age in African-Americans.

CONCLUSIONS

Microscopic foci of HGPIN can be documented in males in the 3rd and 4th decades with the lesion becoming more extensive in older men. The finding that HGPIN is both more prevalent and its more diffuse form appears earlier in African-Americans, indicates a potentially important role for this lesion in the race-related discrepancies associated with this disease.

Local tumor irradiation augments the response to IL-2 therapy in a murine renal adenocarcinoma

We have previously demonstrated that local tumor irradiation effectively enhanced the therapeutic effect of IL-2 therapy on pulmonary metastases from a murine renal adenocarcinoma, Renca. Irradiation with 300 rad to the left lung only, followed by systemic IL-2 therapy, results in increased tumor reduction in both lungs, suggesting that radiation enhances the systemic effect of immunotherapy. In this study, we show that irradiation of the tumor-bearing organ is essential for the combined effect of both modalities. This effect is radiation dose-dependent as increases in the radiation dosage result in greater tumor reduction in the irradiated field as well as systemically in nonirradiated fields when combined with immunotherapy. We find that irradiation has a direct inhibitory effect on Renca cell growth in vitro. Irradiation of Renca cells also causes an upregulation in H-2Kd class I MHC antigen detectable at 300 rad and more pronounced with 800 rad. By in vivo selective depletion of lymphocyte subsets, we demonstrate the involvement of Lyt-2+ and L3T4+ T cell subsets and AsGM1+ cells, including NK cells, in the antitumor effect mediated by tumor irradiation and IL-2 therapy. Immunohistochemistry studies, performed on lung sections, showed a significant infiltration of CD3+ T cells and macrophages in the tumor nodules following treatment with tumor irradiation and IL-2 therapy. Our studies indicate that the mechanism of interaction between tumor irradiation and immunotherapy may include radiation-induced alterations in the tumor growth and antigenicity which may enhance or trigger an anti-tumor response elicited by IL-2 and mediated by T cells, AsGM1+ cells, and macrophages.

Epidemiology of high grade prostatic intraepithelial neoplasia

The prevalence of high grade prostatic intraepithelial neoplasia (HGPIN), the age at which this lesion starts and the potential racial or ethnic differences in its distribution are poorly documented. HGPIN is becoming increasingly implicated as a premalignant lesion for clinically significant prostatic carcinoma (PCa) with mounting evidence linking it to carcinoma according to morphologic immunohistochemical and recent genomic studies. We describe our experience with the age and race distribution of HGPIN resulting from two study populations of African-American (AA) and Caucasian (C) males. The first component of this report describes an autopsy study aimed at determining the prevalence of latent PCa and HGPIN in AA and C men 20 years of age or older; 370 (218 AA and 152 C) consecutive step-sectioned, totally embedded prostate glands were microscopically evaluated and mapped for HGPIN and PCa. HGPIN was first identified in the third decade and increased steadily with age. Latent PCa increased steadily with age with no significant difference in the prevalence between AA and C males in any age group (3rd to 8th decades). HGPIN, on the other hand, was more prevalent in AA men with 18, 31, 69, 78 and 86% in their 4th, 5th, 6th, 7th and 8th decades harboring the lesion. The corresponding figures for C men were 14, 21, 38, 50 and 63% respectively. When HGPIN was quantitated as focal and extensive according to the degree of glandular involvement, extensive HGPIN appeared earlier in AA males under 60 years of age compared to C males cohort. The difference in age distribution appeared to follow a chronological pattern, with HGPIN in AA preceding that of C males by approximately a decade. The second component of this report describes a surgical series of 345 consecutive radical prostatectomies from patients (155 AA and 190 C) with clinically localized PCa, which were thoroughly evaluated microscopically by two urologic pathologists. Similar to the findings in the autopsy study, extensive HGPIN was more prevalent in AA men 60 years of age or younger (57% vs. 33%). In both races, the mean percentage of the gland involved by HGPIN decreased with advancing age in contrast to the mean tumor volume that increased with patient age. These findings indicating a different prevalence of HGPIN in the two racial groups may help explain the higher incidence of prostatic cancer in African-Americans.

Elevated 12-lipoxygenase mRNA expression correlates with advanced stage and poor differentiation of human prostate cancer

OBJECTIVES

Prostate cancer is the most frequently diagnosed cancer and the second leading cause of cancer death in males in the United States. The mortality is due mainly to distant metastasis. Therefore, predicting the prognosis of prostate cancer patients is an important clinical problem. Previously, we demonstrated that a 12-lipoxygenase (12-LOX) metabolite of arachidonic acid, 12(S)-hydroxyeicosatetraenoic acid, enhances the invasiveness of prostate cancer cells and that a 12-LOX-selective inhibitor [N-benzyl-N-hydroxy-5-phenylpentanamide] reduces experimental metastasis in animal model systems. In this study, we investigated the potential of 12-LOX as a predictor for the aggressiveness of prostate cancer.

METHODS

The mRNA expression level of 12-LOX in 122 matching prostate normal and cancerous tissues were measured by quantitative reverse transcription- polymerase chain reaction. Possible association between 12-LOX expression and histologic grade, pathologic and clinical stage, margin positivity, age, and race was analyzed.

RESULTS

12-LOX mRNA levels were elevated in cancer cells and the expression associated with poor differentiation and invasiveness of prostate cancer. Overall, 46 (38%) of 122 evaluable patients showed elevated levels of 12-LOX mRNA in prostate cancer tissues compared with the matching normal tissues. A statistically significantly greater number of cases were found to have an elevated level of 12-LOX among T3, high grade, and surgical margin-positive than T2, intermediate, and low grade, and surgical margin-negative prostatic adenocarcinomas.

CONCLUSIONS

Our data suggest that elevation of 12-LOX mRNA expression occurs more frequently in advanced stage, high-grade prostate cancer and that 12-LOX may serve as an indicator for progression and prognosis of prostate cancer. This enzyme also may be a novel target for the development of anti-invasive and antimetastatic agents.

Radiation-induced effects on murine kidney tumor cells: role in the interaction of local irradiation and immunotherapy

Local tumor irradiation enhances the effect of interleukin-2 (IL-2) therapy in the Renca murine renal adenocarcinoma model. To investigate the mechanism(s) of this interaction, we studied the in vitro and in vivo effects of irradiation on the tumor cells. Tumor cells from in situ irradiated renal tumors had diminished proliferation in vitro. A similar growth inhibition was noted following injection of irradiated Renca cells into naive mice, but this effect could be overcome by injecting more cells. Histologic evaluation of tumors derived from irradiated cells revealed a decrease in mitosis and an increase in multinucleated giant cells, apoptosis and micronecrosis. The presence of irradiated tumor reduced the growth of nonirradiated tumor cells when both were injected into separate flanks of the same animal, suggesting that irradiated tumor cells may trigger a systemic antitumor response. Interleukin-2 therapy given after injection of irradiated tumor cells caused a significant increase in leukocytic infiltrates and micronecrosis. Our findings indicate that radiation directly affects tumor growth and induces a systemic mechanism which could be enhanced by IL-2.

Intralesional treatment of established murine primary renal tumor with interleukin-4: localized effect on primary tumor with no impact on metastases

In an effort to develop new strategies for immunotherapy of metastatic renal cell carcinoma, we investigated the therapeutic potential of interleukin-4 in a visceral renal tumor using the murine Renca renal adenocarcinoma model. Renca cells were implanted underneath the renal capsule of Balb/c mice to induce a primary tumor that spontaneously metastasized to several organs. Established primary renal tumors 4 to 6 mm. in diameter were treated by intralesional administration of recombinant murine interleukin-4 (IL-4). This treatment caused a marked inhibition of the primary tumor growth but had little effect on the progression of metastases in the liver, mesentery and lungs. Immunohistochemistry studies performed on renal tumor sections showed a macrophage infiltration that became predominant 7 days after IL-4 treatment. CD8+ T cells were also observed at the periphery and within the tumor. These data suggest that IL-4 mediated a potent antitumor effect when administered intralesionally although its effects remained localized with no impact on metastases at distant sites. Interleukin-4 antitumor activity seems to be mediated by recruitment of macrophages and T cells in the tumor.

Systemic treatment with interleukin-4 induces regression of pulmonary metastases in a murine renal cell carcinoma model

Advanced metastatic renal cell carcinoma has been shown to be responsive to immunotherapy but the response rate is still limited. We have investigated the therapeutic potential of systemic interleukin-4 (IL-4) administration for the treatment of pulmonary metastases in the murine Renca renal adenocarcinoma model. Renca cells were injected iv in Balb/c mice to induce multiple pulmonary tumor nodules. From Day 5, Renca-bearing mice were treated with two daily injections of recombinant murine IL-4 for 5 consecutive days. IL-4 treatment induced a significant reduction in the number of lung metastases in a dose-dependent manner and significantly augmented the survival of treated animals. Immunohistochemistry studies, performed on lung sections, showed macrophage and CD8+ T cell infiltration in the tumor nodules 1 day after the end of IL-4 treatment. The CD8 infiltration increased by Day 7 after IL-4 treatment. Granulocyte infiltration was not detectable. To clarify further the role of the immune system in IL-4 anti-tumor effect, mice were depleted of lymphocyte subpopulations by in vivo injections of specific antibodies prior to treatment with IL-4. Depletion of CD8+ T cells or AsGM1+ cells abrogated the effect of IL-4 on lung metastases, whereas depletion of CD4+ T cells had no impact. These data indicate that CD8+ T cells and AsGM1+ cells are involved in IL-4-induced regression of established renal cell carcinoma.

Role of surgery in managing local recurrence following external-beam radiation therapy

Salvage surgery for radiation failure in prostate cancer has improved over the last 10 to 15 years owing to earlier detection of failure and better selection of patients. Regardless of the percentage of complications associated with this procedure, it presents the only viable alternative for potential cure of patients failing radiation therapy.

Renal cell carcinoma arising in a regressed multicystic dysplastic kidney

Controversy surrounds the management of multicystic dysplastic kidney. Recent advances in radiological imaging have resulted in a higher incidence of its detection, and they provide an accurate noninvasive means of diagnosis and followup. Consequently, the need for surgical removal of these lesions is being reevaluated. We report a case of renal cell carcinoma arising from solid renal dysplasia associated with a regressed multicystic dysplastic kidney. We emphasize the potential risk of nonoperative management of these lesions and further define the spectrum of malignant degeneration associated with renal dysplasia.

Comparative analysis of epidermal growth factor receptor gene expression and protein product in benign, premalignant, and malignant prostate tissue

In order to more clearly define the status of epidermal growth factor receptor (EGFR) in prostate cancer, expression of EGFR transcript and protein was analyzed in paired samples of benign and malignant tissues from 30 radical prostatectomy specimens. Prostate tumors and high grade prostatic intraepithelial neoplasias (PINs) expressed significantly less EGFR protein than benign tissues or low grade PINs (P < 0.001). Expression of EGFR mRNA was analyzed in a subset of the same samples, and was higher in more prostate tumors than benign specimens (P < 0.05). However, differences in mean mRNA expression between malignant and benign tissues were not significant. EGFR mRNA was expressed at moderate or low levels in equivalent numbers of PIN lesions. These results suggest that, although EGFR mRNA expression is somewhat elevated in prostate tumors, EGFR protein expression may be down-regulated in the same malignant tissues. Furthermore, our data demonstrate phenotypic similarity between prostate tumors and high grade PIN at the level of EGFR protein expression.

Fluorescence in situ hybridization analysis of 8p allelic loss and chromosome 8 instability in human prostate cancer

Cytogenetic and molecular biological studies have demonstrated deletion of sequences that map to the short arm of chromosome 8 (8p) in tumors from several organ systems, including sequences that map within or near 8p22 in human prostate tumors. Recent studies in our laboratory have suggested that deletion of sequences on 8p may be concurrent with alterations in dosage for chromosome 8. In order to further investigate this finding, the present study has applied fluorescence in situ hybridization (FISH) techniques to determine the status of chromosome 8 in prostate tumors that have undergone deletion of sequences at 8p22. Dosage of 8p22 sequences was assayed utilizing unique sequence cosmid DNA probes by FISH and confirmed by amplification of microsatellite sequences by polymerase chain reaction (PCR). Chromosome 8 dosage was assayed by FISH utilizing both unique sequence cosmid probe DNA (specific to the 8q13.1-q13.3 chromosomal region) and pericentromeric probe DNA. FISH analysis of 10 specimens of normal or benign prostatic hyperplasia tissues paired with 9 tumor and one prostatic intraepithelial neoplasia tissues from the same patients for dosage at 8p, 8cen, and 8q, and PCR analysis for dosage at 8p, demonstrated that (a) FISH provided a more precise means of evaluating allelic loss than PCR in prostate tissue; (b) 8p22 sequence losses occurred frequently in prostate tumors; (c) 8p22 sequence losses were most often detected in the absence of 8cen or 8q sequence dosage alterations, although they were sometimes accompanied by gain or loss of 8cen or 8q sequences; and (d) the pattern of 8p22 sequence losses was most often widespread rather than focal. This study is the first to describe FISH analysis of interphase nuclei within tissue sections using cosmid probe DNAs.

Expansion of activated lymphocytes obtained from renal cell carcinoma in an automated hollow fiber bioreactor

Immunotherapy using IL-2 alone or combined with activated lymphocytes has been promising for metastatic renal cell carcinoma. Cytotoxic lymphocytes can be isolated from tumors, expanded in vitro with IL-2, and adoptively transferred back into the tumor-bearing host. These cells can also be transduced with the genes coding for cytokines for local delivery to tumor sites. A major drawback in adoptive immunotherapy is the cumbersome and expensive culture technology associated with the growth of large numbers of cells required for their therapeutic effect. To reduce the cost, resources, and manpower, we have developed the methodology for lymphocyte activation and expansion in the automated hollow fiber bioreactor IMMUNO*STAR Cell Expander (ACT BIOMEDICAL, INC). Tumor Infiltrating Lymphocytes (TIL) isolated from human renal cell carcinoma tumor specimens were inoculated at a number of 10(8) cells in a small bioreactor of 30 ml extracapillary space volume. We have determined the medium flow rates and culture conditions to obtain a significant and repeated expansion of TIL at weekly intervals. The lymphocytes cultured in the bioreactor demonstrated the same phenotype and cytotoxic activity as those expanded in parallel in tissue culture plates. Lymphocyte expansion in the hollow fiber bioreactor required lower volumes of medium, human serum, IL-2 and minimal labor. This technology may facilitate the use of adoptive immunotherapy for the treatment of refractory malignancies.

Allelic loss in locally metastatic, multisampled prostate cancer

In order to determine whether retention or loss of potential tumor suppressor loci that map to 8p, 10q, or 16q reflect genetic relationships among prostatic intraepithelial neoplasias (PINs), multicentric primary prostatic cancers, and regional lymph node metastases or are associated with the metastatic phenotype, we analyzed 19 cases of locally metastatic prostate carcinoma (stage D1) utilizing polymerase chain reaction techniques. In each case, tissue samples from metastatic tumor, the (dominant) primary tumor, and nonneoplastic prostatic tissue were examined. In selected cases, allelic loss in additional tumor foci, separate from the dominant tumor nodule, and areas of PIN were examined. Allelic loss of sequences on 8p, 10q, and 16q were observed in 20-29% of PINs, 18-42% of primary tumors, and 8-25% of metastatic tumors. Discrepancies in sequence dosage between histological components were most pronounced for 8p sequences, especially between the dominant tumor nodule and metastatic deposits in cases in which > or = 3 separate tumor foci/gland were identified. These results suggest that putative premalignant lesions, moderately or poorly differentiated, geographically separate primary tumor foci, and metastases within morphologically "complex" prostates (those with > or = 3 foci/gland) are likely to be more discordant for sequence dosage at 8p than those within "simpler" glands (< 3 foci/gland). Also, our results suggest that lymph node metastases may be genetically related to either the dominant or additional primary tumor foci in more complex prostates and that accumulation of genetic aberration may differ in primary and metastatic lesions.