Murine ferritin heavy chain: isolation and characterization of a functional gene

A mouse liver genomic library screened with a full-length cDNA encoding murine ferritin heavy chain (mFHC) [Torti et al., J. Biol. Chem. 263 (1988) 12638-12644] yielded a functional genomic clone mFHC. The genomic clone isolated included a region of approximately 3 kb containing four exons and three introns. Sequence comparisons of the mouse genomic clone with other genomic clones from rat, human and chicken showed a high degree of similarity among species in the coding regions. Introns and flanking sequences were less conserved. However, comparison of mFHC promoter elements with FHC genes from other species revealed common elements. Analysis of the genomic structure of FHC suggested the presence of pseudogenes. S1 nuclease analysis, however, confirmed that this mouse clone, when transfected into human MRC-5 fibroblasts, was transcribed, indicating that this clone contains an FHC functional gene.

Doxorubicin selectively inhibits muscle gene expression in cardiac muscle cells in vivo and in vitro

The anthracycline antibiotic doxorubicin produces a characteristic myopathy in cardiac muscle that limits its use in cancer therapy. We have shown in cultured neonatal rat cardiac muscle cells that doxorubicin treatment resulted in a rapid, selective decrease in the expression of muscle-specific genes, which preceded other changes characteristic of doxorubicin cardiomyopathy. Doxorubicin selectively and dramatically decreased the levels of mRNA for the sarcomeric genes, alpha-actin, troponin I, and myosin light chain 2, as well as the muscle-specific, but nonsarcomeric M isoform of creatine kinase. However, doxorubicin did not affect nonmuscle gene transcripts (pyruvate kinase, ferritin heavy chain, and beta-actin). Actinomycin D, an inhibitor of DNA-dependent RNA polymerase, did not show a similar selective decrease of muscle-specific mRNAs but, rather, produced a nonspecific, dose-dependent decrease of muscle and nonmuscle transcripts. The doxorubicin effect on muscle gene expression was limited to cardiac muscle; cultured skeletal myocytes were resistant to the effects of doxorubicin at 100-fold greater doses than those causing changes in mRNA levels in cardiac muscle cells. These effects of doxorubicin were reproduced in vivo; rats injected with doxorubicin showed a dose-dependent decrease in the levels of mRNAs for alpha-actin, troponin I, myosin light chain 2, and M isoform of creatine kinase in cardiac but not skeletal muscle. These selective changes in gene expression in cardiocyte cultures and cardiac muscle precede classical ultrastructural changes and may explain the myofibrillar loss that characterizes doxorubicin cardiac injury.

Interleukin 1 induces ferritin heavy chain in human muscle cells

Interleukin 1 alpha (IL-1) and tumor necrosis factor alpha (TNF) are two monokines which play a prominent role in the response to inflammation and injury. We recently observed that TNF leads to an increase in the synthesis of the heavy chain of ferritin, suggesting that TNF may be involved in iron homeostasis (Torti et al. (1988) J. Biol. Chem. 263, 12638-12644). The experiments reported here demonstrate that in cultured human muscle cells, IL-1 induces ferritin H mRNA and protein as effectively as TNF. TNF and IL-1 were additive in their effects on ferritin H expression, and IL-1 induction of ferritin H was not blocked by anti-TNF antibodies. Ferritin H induction was a specific response not observed with beta or gamma interferon, nor with transforming growth factor beta. Both differentiated myotubes as well as myoblasts responded to IL-1 with the induction of ferritin H. These results suggest that monokine-mediated alterations in the subunit composition of the ferritin molecule may be of biological relevance in the response to inflammation and injury.

Evidence for two mechanisms by which tumor necrosis factor kills cells

Tumor necrosis factor (TNF) can inhibit the differentiation of preadipocytes to adipocytes and will revert differentiated adipocytes to the preadipocyte state. TNF is not toxic to either adipocytes or preadipocytes when used alone but is highly toxic to these cells when used in conjunction with cycloheximide, yielding virtually 100% killing within 4-6 h of treatment. A cell line (TA1 R-6) was isolated which is resistant to the combined toxic effects of TNF and cycloheximide. This cell line is stable and, unlike the parental cell line, does not morphologically differentiate to adipocytes or express adipocyte-specific mRNAs. It has a more transformed appearance and growth pattern and, while resistant to the toxic effects of TNF and cycloheximide in a 6-h assay, has become sensitive to cytotoxicity induced by TNF used alone in a 3-day assay. The adipocyte differentiation-inducing agents, dexamethasone and indomethacin, block the cytotoxicity induced by TNF alone in the TA1 R-6 line but do not block the rapid cytotoxicity of TNF and cycloheximide in the parental line. These results provide both genetic and pharmacologic evidence that there are at least two distinct or overlapping pathways by which TNF mediates its effects.

Modulation of adipocyte differentiation by tumor necrosis factor and transforming growth factor beta

Cultured TA1 adipocytes treated with tumor necrosis factor alpha (TNF) lose intracytoplasmic lipid and, over a period of days, come to resemble their predifferentiated progenitors (preadipocytes). To examine the extent to which this phenotypic reversion represents a return to a less differentiated cell, we examined three major characteristics that distinguish preadipocytes from adipocytes: (a) pattern of gene expression; (b) hormonal requirement for accelerated adipogenesis; and (c) pattern of protein synthesis. We found that within hours of TNF addition to adipocytes, mRNAs for genes whose expression is augmented during adipogenesis decreased to predifferentiated levels; in addition, like preadipocytes, TNF-treated adipocytes required exposure to hormones to accelerate adipogenesis. Further, the pattern of protein synthesis seen on polyacrylamide gels reverted to that seen before differentiation. Transforming growth factor-beta (TGF-beta) also caused a rapid decrease in expression of adipose genes when added to fully differentiated cells, an effect that was achieved by treatment with either TGF-beta 1 or TGF-beta 2. These effects were seen in the absence of a demonstrable proliferative response to either TNF or TGF-beta. Thus characteristics that define the "terminally" differentiated state in adipocytes are subject to modulation by environmental influences.

Efficient scheduling of cystoscopies in monitoring for recurrent bladder cancer

Proper timing for repeated evaluations is difficult to assess. The authors analyzed scheduling of cystoscopy to monitor patients for detection of recurrent bladder cancer assuming that 1) minimizing tumor detection delay helps prevent cancer morbidities; 2) only limited numbers of cystoscopies are available; 3) prediction of recurrence or progression to invasive cancer is uncertain; 4) future tumors recur according to a Poisson process. Assumptions 3 and 4 permit estimation of each patient's recurrence rate. Thus, patients may be compared according to their relative risks of future tumors. With these assumptions, nonlinear optimization theory was used to calculate monitoring schedules for a model practice. Given 5.4 available visits per week per 100 patients, cystoscopy was recommended in 9-11 weeks for high-risk patients and in 30-40 weeks for low-risk patients, depending on stages, grades, and numbers of previous tumors. In contrast, standard cystoscopy was recommended in 13, 26, or 52 weeks, depending only on time elapsed since last recurrence. The calculated schedule implied an average detection delay for potentially invasive tumors of eight weeks, while standard practice led to detection delays of 11 weeks (38% worse). These results suggest that inclusion of each patient's tumor history in an optimization approach may improve follow-up care for patients who have superficial bladder cancers. This approach is being evaluated in a larger clinical setting.

Carcinoma of the prostate: pathology, staging, and treatment

Prostate cancer is the most common malignancy affecting American men over the age of 50. Its incidence increases with each decade. It is usually discovered by rectal examination performed during physical examination or incidentally found on histologic sections of a prostate removed to alleviate urinary obstructive symptoms. About 50% of patients have clinically localized disease at presentation. The majority of prostate cancers grow slowly, metastasize late, and are not the primary cause of death. Before recommending treatment to a patient with prostate cancer, the treating physician should assess the extent of malignancy and determine which therapy, if any, would favorably influence the course of disease with the least influence on the general quality of life. Patients with disease limited to the prostate are offered curative therapy with either radical prostatectomy or radiation therapy. Those with locally extensive disease are treated with external beam irradiation or with androgen ablation. Metastatic disease is treated by androgen ablation. Chemotherapy is reserved for those patients who fail hormonal treatment.

Brain metastases from transitional cell carcinoma of the bladder

We present our experience with 4 patients with transitional cell carcinoma of the bladder and brain metastases. In all 4 cases a solitary intracranial metastasis occurred. In 3 patients this represented the first site of recurrent disease following systemic chemotherapy. Aggressive therapy of the brain metastases was instituted in 3 patients, including external beam radiation and in 2 cases surgical resection. Although all patients died only 3 died as a result of metastatic transitional cell carcinoma, including 2 who died as a direct result of intracranial disease. A review of the literature suggests an increasing incidence of brain metastases from transitional cell carcinoma of the bladder with the advent of more aggressive therapy for bladder cancer, which includes radical surgery for high stage disease and combination chemotherapy. Aggressive intervention for solitary brain metastases from transitional cell carcinoma can relieve neurological dysfunction and may prolong survival.

The molecular cloning and characterization of murine ferritin heavy chain, a tumor necrosis factor-inducible gene

Ferritin is a ubiquitous and highly conserved protein which plays a major role in iron homeostasis. We have identified and sequenced a full-length cDNA for murine ferritin heavy chain. The isolated cDNA is 819 nucleotides in length. It includes 546 nucleotides which encode a protein of 182 amino acids, a 5' noncoding sequence of 120 nucleotides, and a 3'-noncoding region of 153 nucleotides. The sequence displays a high degree of homology to human ferritin H, and includes a portion of the iron-responsive element conserved in chick, frog, and human ferritin. Tumor necrosis factor (TNF), a cytokine which mediates elements of the stress response, induces expression of ferritin H mRNA. Both mouse TA1 adipocytes and human muscle cells increase expression of ferritin H mRNA 4-6-fold after 48 h exposure to TNF. This increase occurs both prior and subsequent to differentiation of adipocytes and muscle cells, and is accompanied by an increase in the synthesis of the ferritin H subunit. These findings suggest a novel role for TNF in iron metabolism.

Tumor necrosis factor inhibits human myogenesis in vitro

We examined the effects of human recombinant tumor necrosis factor-alpha (TNF) on human primary myoblasts. When added to proliferating myoblasts, TNF inhibited the expression of alpha-cardiac actin, a muscle-specific gene whose expression is observed at low levels in human myoblasts. TNF also inhibited muscle differentiation as measured by several parameters, including cell fusion and the expression of other muscle-specific genes, such as alpha-skeletal actin and myosin heavy chain. Muscle cells were sensitive to TNF in a narrow temporal window of differentiation. Northern (RNA) blot and immunofluorescence analyses revealed that human muscle gene expression became unresponsive to TNF coincident with myoblast differentiation. When TNF was added to differentiated myotubes, there was no effect on muscle gene expression. In contrast, TNF-inducible mRNAs such as interferon beta-2 still responded, suggesting that the signal mediated by TNF binding to its receptor had no effect on muscle-specific genes after differentiation.

Alpha-interferon in superficial bladder cancer: a Northern California Oncology Group Study

Thirty-five patients with superficial transitional carcinoma of the bladder were treated intravesically with escalating doses of recombinant alpha-2-interferon administered weekly for 8 weeks. Of the 19 patients with high-grade intraepithelial neoplasia (17 carcinoma in situ [CIS], two severe dysplasia, all cytology positive), six (32%) had complete resolution of all histologic and cytologic evidence of disease (complete response). An additional three patients (16%) had complete resolution of CIS, but the interval appearance of a low-grade transitional cell neoplasm. Five (26%) had a partial response (complete resolution of all evidence of CIS on multiple bladder biopsies but persistently positive cytologic preparations). Sixteen patients with recurrent papillary tumors and extensive prior therapy were also treated. Four (25%) had a complete response. Twenty-three of the 35 patients had prior intravesical therapy. Seven of the 23 (30%) patients with prior intravesical chemotherapy or immunotherapy had a complete or partial response to interferon, while eight of the 12 patients (67%) without prior intravesical treatment responded. These responses were achieved with minimal local and systemic toxicity. Of the ten complete responders, five remain in continuous unmaintained remission for 18+ to 37+ months. Intracavitary alpha-2-interferon is an effective new treatment for some patients with bladder cancer.

Failure of adjuvant chemotherapy in testicular cancer

Two cases of failure of adjuvant chemotherapy after retroperitoneal lymph node dissection of Stage II nonseminomatous germ cell tumors are described. In both cases, initial surgical resection was complete, and two cycles of chemotherapy with cisplatin, vinblastine, and bleomycin were administered in an appropriate dose and schedule. Although one patient remains without evidence of disease 12 months after initiation of salvage chemotherapy with cisplatin, etoposide, and bleomycin, the other patient died of progressive disease despite intensive treatment with cisplatin and etoposide. Adjuvant therapy for Stage II germ cell tumors is not conventional treatment, and should be applied only in investigative settings where the long term effects and toxicity can be monitored, and does not reduce the need for frequent and thorough follow-up of treated patients.

Approaches to the treatment of bladder cancer at Stanford

The treatment of bladder cancer is one of the most active areas of clinical cancer research. The use of new classes of intravesical agents, such as the interferons, and analogues of effective intravesical chemotherapies, such as epirubicin, the 4-epimer of doxorubicin, show promise of controlling the sequela of this common urologic problem. In metastatic transitional cell carcinoma, the CMV regimen holds promise of palliation for many and or long-term remission for some patients with advanced bladder cancer.

Superficial bladder cancer. Risk of recurrence and potential role for interferon therapy

Superficial bladder tumors--cancer in situ (CIS) and papillary transitional carcinoma of the bladder--are the most frequent presentations of bladder cancer, the second most common disease of the urethelial tract. These superficial tumors demonstrate a tendency to recur, either at the same stage and grade or as deeply invasive tumors. To some extent, the likelihood of tumor recurrence can be predicted, based on certain risk factors. Furthermore, the probability of recurrence can be altered through appropriate clinical interventions. A review of the literature, much of which is preliminary, suggests that interferon therapy for bladder cancer may modify the biologic behavior of this disease and provide clinical benefit for some patients.

Superficial bladder cancer: the primacy of grade in the development of invasive disease

Tumor characteristics thought to predict for development of deep muscle invasion after resection of superficial bladder cancer were retrospectively analyzed in 252 patients with transitional cell carcinoma of the bladder at Stanford University Medical Center. Stage 0 patients accounted for 190 of the patient population (75.5%), while stage A and B1 comprised 51 (20%) and 11 (4.5%), respectively. The median follow-up time was 62 months. Forty-three patients subsequently developed deep muscle invasion; these included 24 (12.6%), 14 (27.5%), and 5 (45.5%) of stage 0, A, and B1 patients (P = .002), or 15 (10%), 15 (9%), and 13 (33%) of grade 1, 2, and 3 tumors (P = .001), respectively. When analyzed by univariate logistic regression, grade (P = .0001) and stage (P = .0118) were significant predictors for invasive disease. Site of tumor and number of tumors at presentation were not significant factors for invasion deep into the bladder wall. When multiple logistic regression was performed, only grade remained as a significant tumor variable to predict for invasive disease (P less than .0091). Risk of invasive disease did not appear to increase with increasing number of recurrences, remaining at approximately an 11% invasion rate through 12 recurrences. In this analysis, grade was the most significant tumor variable in superficial bladder cancer predicting for the development of invasive carcinoma. Future clinical trials for definitive or adjuvant therapy of this disease must stratify for this variable.

Hormonal control of adipogenesis

The concept that hormonal substances can alter the expression of entire developmental programs is in itself not particularly new. The ability to define conditions under which a specific hormone can precociously activate the differentiation of a well-defined population of cells and under which another hormone can both block and reverse such a developmental progression, however, provides a major step forward toward unraveling the biochemical events that define the transition from a committed precursor to a fully differentiated cell. Further analysis of the molecular events initiated by glucocorticoids and TNF should provide insights into the control of adipogenesis and may generate a foundation for understanding the mechanisms by which other cells enter a particular differentiative lineage. In a more applied sense, such knowledge may also provide a rational approach to controlling metabolic disease syndromes related to adipogenesis gone awry such as obesity-associated diabetes and cachexia.

Superficial carcinoma of the bladder: natural history and the role of interferons

Superficial transitional cell carcinoma of the bladder is a chronic disease. Patients face a lifetime with the potential for further neoplastic manifestations--the recurrence of either superficial or deeply invasive tumor. To some extent, the likelihood of disease recurrence can be predicted. Further, certain clinical interventions can alter the probability of tumor recurrence. This paper focuses on those patient and tumor characteristics that predict for the propensity to develop recurrent disease, with emphasis on the potential of the interferons to both treat this disease and to modify its natural history.

Hormonal risk factors in testicular cancer. A case-control study

The authors interviewed 273 northern California testicular cancer cases aged 40 and under diagnosed between 1976 and 1981, their mothers, and matched peer controls and their mothers on prenatal hormone exposure and other variables. Included was a population-based substudy (1979-1981) of all interviewable cases reported to the San Francisco Bay Area Surveillance, Epidemiology, and End Results registry. They found odds ratios (OR) of from 8.3 (sons' report) to 4.5 (mothers' report) associated with cryptorchidism, but found no association with mothers' hormone exposure or diethylstilbestrol exposure in pregnancy. They also found a significant association with lower age at puberty (OR = 2.0); a marginally significant association with mothers' breast cancer (OR = 2.9, p = 0.054); and a significant protective effect of reported mononucleosis (OR = 0.6). These associations remained strong in the population-based substudy. When cases were divided by histology, strong and specific associations of earlier puberty (OR = 2.3) and mothers' breast cancer (OR = 4.4) with nonseminomatous cancer, and of reported mononucleosis (OR = 0.3) with seminomatous cancer, were found. These observations suggest that 1) prenatal exogenous hormone exposure does not account for a significant fraction of testicular cancer, 2) a cluster of "breast-cancer-like" risk factors are associated with nonseminomas, and 3) there is some genetic risk of nonseminomas.

Cardiotoxicity of epirubicin and doxorubicin: assessment by endomyocardial biopsy

Forty-two evaluable endomyocardial biopsies were obtained from 29 patients treated with epirubicin, the 4'-epimer of doxorubicin in cumulative doses ranging from 147 mg/m2 to 888 mg/m2. In this study of the Northern California Oncology Group, myofibrillar loss and sarcoplasmic vacuolization were identified and shown to be identical to those previously described for doxorubicin. However, when these biopsies were compared to 119 biopsies obtained from 98 patients treated with doxorubicin, milligram for milligram, epirubicin caused less endomyocardial injury than doxorubicin (P = 0.0013). Age, sex, type of primary malignancy, prior cardiac disease, and hypertension did not influence the degree of histologically demonstrated anthracycline injury induced by epirubicin.