A randomized, double blind, Phase III trial using oral beta-carotene supplementation for women with high-grade cervical intraepithelial neoplasia.

To evaluate the effect of daily beta-carotene (30 mg) versus placebo over a 2-year period on cervical intraepithelial neoplasia (CIN) 2 and 3 lesions. Human papillomavirus (HPV) typing was done to determine whether lesion regression was related to HPV. Micronutrient levels were measured to determine whether levels were predictive of regression. Variables that influence the risk of HPV infection and CIN, such as cigarette smoking and sexual behavior, were evaluated. Women were randomized to beta-carotene or placebo, with cytology and colposcopy every 3 months. Cervical biopsies were performed before treatment and after 6 and 24 months to evaluate response. Persistence of or progression to CIN 3 resulted in removal from the study, whereas treatment continued for 2 years on all others. The presence and type of HPV was determined by PCR. Response was defined as an improvement in CIN by 2 grades. Mantel-Haenszel chi(2) test was used to analyze response to treatment. Fisher's exact test was used to determine the effect of HPV and CIN grade on response Wilcoxon's rank-sum tests were used to compare micronutrient levels between groups. Twenty-one of 124 enrolled women were not randomized because they either moved, became pregnant, voluntarily withdrew, or the pathological review of their initial cervical biopsies did not confirm CIN 2 or 3. Of the remaining 103 women, 33 experienced lesion regression, 45 had persistent or progressive disease, and 25 women did not complete the study and were considered nonresponders in the final analysis. The overall regression rate (32%) was similar between treatment arms and when stratified for CIN grade. Data on 99 women with HPV typing showed that 77% were HPV-positive and 23% HPV-negative at enrollment. HPV-positive lesions were subdivided into indeterminate-, low-, and high-risk categories; the response rate was highest for women with no HPV detected (61%), lower for indeterminate/low-risk (30%), and lowest for high-risk (18%; P =.001). CIN regression was negatively correlated with retinol levels. In conclusion, beta-carotene does not enhance the regression of high-grade CIN, especially in HPV-positive subjects.

Effect of retinol in preventing squamous cell skin cancer in moderate-risk subjects: a randomized, double-blind, controlled trial. Southwest Skin Cancer Prevention Study Group.

We conducted a randomized, double-blind, controlled trial to examine the efficacy of retinol supplementation on the incidence of first new nonmelanoma skin cancer in moderate-risk subjects. A total of 2297 free-living subjects were enrolled; subjects resided in Arizona (median age, 63 years) and had a history of more than 10 actinic keratoses and at most 2 squamous cell carcinoma (SCC) or basal cell carcinoma (BCC) skin cancers. Subjects were randomly assigned to receive oral retinol (25,000 IU) or placebo supplementation daily for up to 5 years. The primary end points for the trial were time to first new SCC or BCC. During a median follow-up time of 3.8 years, we found that 526 subjects had a first new skin cancer. Comparing retinol-supplemented subjects with placebo-supplemented subjects showed a hazard ratio for first new SCC of 0.74 (95% confidence interval, 0.56-0.99; P = 0.04). The hazard ratio of first new BCC for the retinol-supplemented subjects compared with those receiving placebo was 1.06 (95% confidence interval, 0.86-1.32; P = 0.36). Potentially adverse symptoms that were judged to be associated with retinol were rare (approximately 1% higher in the retinol group than in the control group). Therefore, we concluded that daily supplementation with 25,000 IU of retinol was effective in preventing SCC, although it did not prevent BCC.

Trial of retinol and isotretinoin in skin cancer prevention: a randomized, double-blind, controlled trial. Southwest Skin Cancer Prevention Study Group.

The objective of this study was to examine the effect of retinol and isotretinoin on the incidence of nonmelanoma skin cancer in high-risk subjects. A total of 525 participants with a history of at least four basal cell carcinomas (BCCs) and/or cutaneous squamous cell carcinomas (SCCs) were entered into a randomized, double-blind, placebo-controlled trial, performed in free-standing study clinics. Participants were randomly assigned to receive oral retinol (25,000 units), isotretinoin (5-10 mg), or placebo supplementation daily for 3 years. The time to first new occurrence of BCC or cutaneous SCC was used as the outcome measure. During the study period, 319 BCCs and 125 cutaneous SCCs were diagnosed clinically and pathologically. There were no differences between those who received retinol, isotretinoin, or the placebo, with regard to the time to first occurrence or to the total number of tumors noted. No beneficial effects were noted with regard to the prevention of nonmelanoma skin cancer with either retinol or isotretinoin.

Involvement of polyamines in selenomethionine induced apoptosis and mitotic alterations in human tumor cells.

The efficacy of dietary selenium supplementation is currently being evaluated in intervention trials. However, the biological mechanisms underlying the cancer chemopreventive effects of selenium supplementation have yet to be elucidated. Selenium metabolism and polyamine biosynthesis are linked in their common requirement for S-adenosylmethionine. Selenomethionine was the predominant form of selenium in the dietary supplement, therefore we evaluated the anti-tumorigenic effects of selenomethionine. We found that selenomethionine inhibited tumor growth (both in A549 lung and HT29 colon cancer cells) in a dose-dependent manner. At 24 and 72 h, polyamine content of A549 and HT29 cancer cell lines was decreased at doses that inhibited 50% of normal growth. Selenomethionine treatment induced apoptosis in both cancer cell lines. Exogenous spermine administration, which replenishes intracellular polyamine levels, prevented selenomethionine induced apoptosis. Selenomethionine administration to the cancer cell lines increased the number of cells in metaphase. This cell cycle effect appeared to be reversed with the co-administration of selenomethionine and spermine. These data suggested that at least part of the anti-carcinogenic effects of selenium supplementation might be due to a depletion in polyamine levels. This depletion of polyamines leads to an induction in apoptosis and perturbations in the cell cycle.

New carotenoid values for foods improve relationship of food frequency questionnaire intake estimates to plasma values.

Carotenoid consumption is of great interest in disease prevention studies. Until recently, carotenoid food composition data have not been available from a single laboratory source with high validity/reliability characteristics. With the availability of a new carotenoid food composition data base, we examined the impact of the new data base on the intake estimates as measured by a food frequency questionnaire and on the relationship of those estimates to plasma values to ascertain what, if any, improvement is achieved through use of the new values. Plasma samples were available for 162 healthy adults participating in cancer prevention studies at the Arizona Cancer Center, including men and women, smokers and nonsmokers. A single laboratory analyzed plasma samples for beta-carotene, alpha-carotene, lutein, and lycopene. All subjects had completed a modified version of the Block food frequency questionnaire, which calculates carotenoids using a literature-based algorithm. A new carotenoid composition data base using recently published data (A.R. Mangels et al., J. Am. Diet. Assoc., 93: 284-296, 1993) was then directly substituted for the Block data base. There were high correlations between intake estimates derived from the two data bases for all four carotenoids (range, r = 0.76-0.96). Average intake estimates based on the Mangels et al. data base were significantly higher for beta-carotene and lycopene; however, correlations between intakes and plasma values were significantly different only for beta-carotene (r = 0.44 for Mangels versus 0.32 for Block, P = 0.015).

beta-Carotene treatment of cervical intraepithelial neoplasia: a phase II study.

The use of Papanicolaou smears for cervical cancer screening has led to an increased detection of preinvasive conditions of the cervix, cervical intraepithelial neoplasia (CIN). Epidemiological studies have shown an association between low levels of dietary beta-carotene and CIN. In this Phase II study, we have explored the effect of p.o. beta-carotene administration on CIN I and II. Patients with documented CIN I or II were treated with 30 mg daily of beta-carotene for 6 months. Response rates were determined at 0, 3, 6, and 12 months with cytology, colposcopy, and/or biopsies. Levels of beta-carotene and vitamin E were determined at the same time intervals in vaginal mucosa cells and serum. Response rates were 18 of 30 (60%), 21 of 30 (70%), and 10 of 30 (33%) at 3, 6, and 12 months, respectively. Significant changes occurred in the serum beta-carotene levels over time. Median levels over 2200 mg/ml were found at 3 and 6 months versus a baseline median level of 111 (P < 0.0001). Significant increases were also noted in the beta-carotene levels of the vaginal mucosa compared to baseline (P = 0.01) and a significant correlation was noted between serum and vaginal beta-carotene levels as well (P < 0.0001). This study indicates that a large percentage of patients with CIN I and II will respond clinically to p.o. beta-carotene supplementation. There is a positive relationship between serum and tissue levels of beta-carotene which suggests that serum levels can be used for monitoring purposes. Because of these encouraging results, prospective randomized studies are ongoing comparing the efficacy of beta-carotene against an untreated control arm.

Exhaled ethane and antioxidant vitamin supplements in active smokers.

To determine the effect of nutritional agents on lipid peroxidation, 10 smokers were given 6 mg beta carotene, 200 IU vitamin E, and 250 mg vitamin C 4 times daily for 3 weeks. Lipid peroxidation was assessed by measuring baseline and postsupplementation levels of exhaled ethane. There was a 29% decrease in mean (+/-SD) exhaled ethane (4.06 +/- 1.49 vs 2.90 +/- 1.29 pmol.kg-1.min-1), with individual levels decreasing in 8 of the 10 smokers (p < 0.05, Wilcoxon sign rank test). Three nonsmokers had very low baseline levels of ethane that did not change with supplementation. Ethane production correlated with active (packs per day) and lifelong (pack-years) tobacco consumption. Also, a strong correlation was found between the decline in ethane output after micronutrient supplementation and the presupplement FEV1. Therefore, antioxidant vitamin supplementation resulted in attenuation of smoking-related lipid peroxidation, and the decreases in ethane production appears to be associated with preserved lung function.

Design and recruitment for retinoid skin cancer prevention (SKICAP) trials. The Southwest Skin Cancer Prevention Study Group.

The retinoid skin cancer prevention (SKICAP) trials are a set of double-blind, randomized, placebo-controlled clinical trials. The SKICAP-actinic keratoses (AK) trial tests the hypothesis that daily supplementation of retinol (25,000 IU) for 5 years reduces the incidence of skin cancers in high-risk individuals, those with a history of greater than ten clinically or pathologically diagnosed AK and, at most, one prior pathologically confirmed cutaneous squamous cell carcinoma (SCC) or basal cell carcinoma (BCC). The SKICAP-SCC/BCC (S/B) trial tests the hypothesis that daily supplementation of retinol (25,000 IU) or 13-cis-retinoic acid (5 or 10 mg) for 3 years reduces skin cancer incidence in very high-risk individuals, those with a history of at least four pathologically confirmed SCCs or BCCs. Between 1984 and 1988, 2800 participants were enrolled at two clinics on the SKICAP-AK trial; and between 1985 and 1990, a total of 719 participants were enrolled at four clinics on the SKICAP-S/B trial. The initial recruitment strategy was referral by dermatologists, but low accrual necessitated the use of other strategies to achieve enrollment goals, which included involving additional clinics and using paid trial-specific advertisements in print and electronic media. Thirteen % of the SKICAP-AK participants and 36% of the SKICAP-S/B participants were enrolled through dermatologist referral, whereas paid advertisements resulted in enrollment of 87% of SKICAP-AK and 43% of SKICAP-S/B participants. A population-based skin cancer registry was used to identify and enroll the remaining 21% of the SKICAP-S/B participants.(ABSTRACT TRUNCATED AT 250 WORDS)

Concentrations and plasma-tissue-diet relationships of carotenoids, retinoids, and tocopherols in humans.

Micronutrients, such as beta-carotene and vitamins A and E, are potential chemopreventive agents; however, their concentrations in human target tissues are largely unknown. Because these micronutrients may exert their action at the site of target tissues, the tissue concentrations of the micronutrients need to be determined. In this cross-sectional study, we have measured the concentrations of seven carotenoids, two retinoids, and two tocopherols in paired plasma, buccal mucosal cells (BMC), and skin samples from 96 healthy subjects (ages 26-82 yrs). The plasma-tissue, as well as the diet-plasma and diet-tissue relationships of the micronutrients, and the impact of various potential confounders on the micronutrient concentrations were evaluated. The micronutrient concentrations of plasma and BMC used in the evaluation were the average of three measurements over a one-month period. Our data indicated that 1) the correlations between the plasma and BMC (Spearman r = 0.40-0.91, p < 0.05) and the plasma and skin (r = 0.24-0.75, p < 0.05) concentrations of most micronutrients were significant in all subjects, suggesting that the status of these micronutrients in the BMC and skin may be estimated from their plasma concentrations; 2) the correlations between the diet and plasma/tissue concentrations of the micronutrients were generally not as strong as the plasma-tissue relationships; the diet-plasma and diet-tissue relationships of the carotenoids were particularly poor in the smokers; 3) the plasma and tissue concentrations of most micronutrients were lower in smokers than in nonsmokers and higher in vitamin supplement users than in nonsupplement users; the differences remained significant after adjustment for age, gender, and diet intake estimates; 4) among the seven carotenoids examined, lycopene was unique, because its concentration was not lower in smokers or higher in supplement users but was inversely associated with age.

Micronutrient concentrations in paired skin and plasma of patients with actinic keratoses: effect of prolonged retinol supplementation.

Much of our knowledge about the relationship between micronutrients and cancer comes from studies in which plasma (serum) micronutrient levels have been correlated with cancer incidence; however, the relationship between the concentrations of micronutrients in the plasma and in the target tissues has not been established. Ninety-three subjects (62 males and 31 females ages 42-86, median age 69) with actinic keratoses were recruited for investigation of this relationship. The subjects were randomly assigned and received placebo or retinol (25,000 IU/day) intervention for 48 to 65 months as part of a skin cancer chemoprevention trial. Shortly before the end of the trial, three fasting plasma samples and one skin biopsy were obtained from each subject. The concentrations of lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, beta-carotene, cis-beta-carotene, retinol, retinyl palmitate, alpha-tocopherol and gamma-tocopherol in the plasma and skin were simultaneously measured using HPLC. The profiles of the eleven micronutrients in the plasma and skin were similar. Lycopene, beta-carotene and alpha-tocopherol were the predominant micronutrients in both plasma and skin, but the ratio of retinyl palmitate to retinol was much greater in the skin than plasma. The three fasting plasma concentrations from the same subject during a one-month period were very consistent; however, the between-person variations were very large. The retinol supplementation caused a significant increase in the plasma concentrations of retinol, retinyl palmitate, lutein and alpha-tocopherol, especially retinyl palmitate as well as the skin concentrations of retinol and retinyl palmitate.(ABSTRACT TRUNCATED AT 250 WORDS)

[Therapeutic effects of Chinese drugs on early renal damage of rats caused by fish bile].

The therapeutic effects of Salvia miltiorrhizae, Typha angustifolia, Rheum palmatum preparations on early renal damage of rats caused by fish bile were observed. These drugs were effective in reducing serum creatinine, urinary NAGase, count of necrosed epithelial cells of proximal tubule and that of glomerular filled with RBC in Bowman's space (P < 0.05), and also effective in increasing creatinine clearance (P < 0.05).

Reduction in plasma or skin alpha-tocopherol concentration with long-term oral administration of beta-carotene in humans and mice.

BACKGROUND: Beta-carotene is one of the most commonly used compounds in clinical trials of chemopreventive agents in various neoplastic diseases. Animal studies, including our own, have documented that dietary beta-carotene can reduce plasma alpha-tocopherol (vitamin E) levels, but few published studies have examined the clinical or pharmacokinetic ramifications of long-term, high-dose beta-carotene regimens on other fat-soluble vitamins such as alpha-tocopherol. PURPOSE: This study was designed to determine the effects of long-term beta-carotene supplementation on plasma concentrations of alpha-tocopherol in normal human subjects and in an experimental C3H/HeN mouse model. METHODS: In a double-blind study, 45 normal subjects were randomly assigned to receive 0 (placebo), 15, 30, 45, or 60 mg of oral beta-carotene daily for approximately 9 months. Monthly plasma samples were collected. Thirty-five C3H/HeN mice were fed a basal diet with or without beta-carotene and treated topically with or without alpha-tocopherol, except for the control mice, which received UV radiation for 27 weeks from week 3 to week 30. Plasma and dorsal skin samples were taken after 40 weeks and were analyzed for alpha-tocopherol and/or beta-carotene by high-performance liquid chromatography. RESULTS: Long-term dietary beta-carotene administration resulted in statistically significant reductions in levels of alpha-tocopherol in the skin and plasma of UV-irradiated mice. In the human study, the decrease in plasma alpha-tocopherol levels was progressive and significant between 6 and 9 months of beta-carotene dosing in all dosage groups. The greatest decrease was observed during the 9th (last) month of dosing, with a decrease of 40% from baseline. All oral beta-carotene doses (15-60 mg/d), however, resulted in similar decreases in steady-state plasma levels of alpha-tocopherol and in only small differences in beta-carotene plasma levels. CONCLUSION: Long-term oral administration of beta-carotene decreased steady-state plasma concentrations of alpha-tocopherol. The lack of a significant dose-response effect between doses of beta-carotene and alpha-tocopherol plasma levels is not unexpected, given the small differences in steady-state beta-carotene plasma levels in the four beta-carotene dose groups. IMPLICATIONS: Studies are needed to determine how long-term beta-carotene dosing influences tissue distribution of dietary alpha-tocopherol. Careful surveillance for this and other potentially harmful nutrient interactions should become part of all long-term intervention studies.

Cumulative reduction of primary skin tumor growth in UV-irradiated mice by the combination of retinyl palmitate and canthaxanthin.

The effects of dietary supplementation with retinyl palmitate, canthaxanthin, or the combination of both, on photocarcinogenesis was determined in pigmented C3H/HeN mice. The basal diet was the American Institute of Nutrition Diet 76A, to which was added 120 IU of retinyl palmitate per g diet, 1% canthaxanthin, or the combination of both. Administration of the diets began 18 weeks before the first UVB radiation (280-320 nm) treatment and continued throughout the study. The UV source was a bank of 6 Westinghouse FS40 lamps which delivered to the mice a total dose of 9.9 x 10(5) J/m2, delivered over 24 weeks. These diets significantly reduced the tumor burden per mouse induced by UV irradiation, however they did not influence tumor incidence. The combination of retinyl palmitate plus canthaxanthin was more effective than either agent alone at reducing autochthonous tumor growth, a result which has not been previously reported.

Bleomycin compatibility with selected intravenous medications.

Three separate in vitro admixture experiments were accomplished with bleomycin and other common parenteral medications. Bleomycin was assayed by a radioimmunoassay procedure. Bleomycin was found to be compatible with a majority of drugs including the aminoglycoside antibiotics, the vinca alkaloid antineoplastics, the antimetabolite fluorouracil, several phosphate salt corticosteroids, diphenhydramine and the anticoagulant heparin sulfate. Incompatible admixtures include the acidic cephalosporin and penicillin-derived antibiotics, the antineoplastics, methotrexate, and mitomycin C, the sodium succinate salt of hydrocortisone as well as ascorbic acid (vitamin C).

Therapeutic synergism of hyperthermia-cis-platinum in a mouse tumor model.

A small-animal model was developed as a guide to whole-body hyperthermia in cancer patiens. Anesthetized DBA/2 mice were secured to a platform, and their hindlimbs were immersed in a 42.3 degrees C water bath for 30-60 minutes. Hindlimb hyperthermia reulted in steady-state rectal and femoral bone marrow and muscle temperatures of 42 degrees C and upper extremity muscle and esophagus temperatures of 41 degrees C. With this hyper thermia technique, the mouse spleen colony assay could be used to quantitate the lethality of hyperthermia and/or cis-dichloro-diammineplatinum(II) (cis-platinum) on clonogenic bone marrow and leukemia cells. Hyperthermia prior to cis-platinum administration increased cis-platinum inhibition of leukemia colony formation as much as 2 logs; however, antileukemia synergism ws greatest when cis-platinum administration immediately preceded hyperthermia and no evidence existd of synergism against normal bone marrow colonies. Correlative in vivo drug uptake studies showed a marked increase in leukemia cell uptake of 195mPt-cis-platinum at elevated temperatures, which suggested a potential mechanism for the apparent antileukemia synergism of cis-platinum and heat.

Carnitine prevention of adriamycin toxicity in mice.

Carnitine, a naturally occurring nontoxic compound which aids the myocardial cell in efficiently meeting energy requirements, has been evaluated as a possible protective agent against acute and chronic adriamycin induced mouse toxicity. We have shown that carnitine treatment significantly decreases both acute high dose and chronic, intermittent, low dose adriamycin associated lethality in normal mice. These protective effects are accomplished without decreasing adriamycin anti-tumor activity or increasing bone marrow toxicity.

Changes in the nuclear volume of rat hypothalamic neurons in old age.

Nuclear volumes (NV) of neurons in the preoptic are (POA), suprachiasmatic nucleus (SC), paraventricular nucleus (PVN), supraoptic nucleus (SO), anterior hypothalamic area (AHA), arcuate nucleus (ARN), ventromedial nucleus (VMN), dorsomedial nucleus (DMN) and lateral mammillary nucleus (ML) were measured in 3.5- to 5-month-old female and male rats and in old female and male rats over 22 months of age. Young adult female rats had larger NV than males in the neurons of all measured areas except for the SC during estrus and the ARN. NV of the hypothalamic neurons of female rats decreased in old age in all measured areas except for the VMN of rats exhibiting prolonged vaginal cornification (PVC). Old male rats showed decreased NV only in the neurons of the SC, SO and ML. The extent of NV decrease of the hypothalamic neurons was not similar in different areas. The sexual difference in neuronal NV in most of the areas disappeared in old age. Only the POA of rats with PVC and the ML of old female rats had larger NV than those of old male rats.

Changes in the uptake of tritiated estradiol in the hypothalamus and adenohypophysis of old female rats.

PIP: The dysfunction of the hypothalamic-pituitary axis of 32 old female rats was elucidated. Old rats were over 20 months of age; young rats were only several months old. Rats were divided into 3 groups according to vaginal smears and ovarian and uterine findings during laparotomy: 1) prolonged vaginal cornification with polyfollicular ovaries (PVC), 2) anestrus with atropic ovaries and uterus (ANE), and 3) prolonged diestrus with hyperluteinized ovaries and hypertropic uterus (pseudopregnancy, PSP). Even 1 week after ovariectomy the uteri of old rats with PVC (11) or PSP (5) were heavier than the uteri of young adults oq old rats with ANE (20). The pituitaries of young rats (32) were lighter than those of old rats (32). In vitro tritiated estradiol uptakes of anterior hypothalamus, adenohypophysis and uterus of old rats with PVC; anterior and posterior hypothalamus, adenohypophysisand uterus of old rats with ANE (10) and adenohypophysis of old rats with PSP were each significantly lower than the corresponding uptakes in the young rats. Further investigation using young rats with induced PSP, indicated that the decreased tritiated estradiol uptake in the adenohypophysis of old PSP rats was due to old age and unrelated to PSP. In vivo tritiated estradiol uptakes of anterior hypothalamus and adenohypophysis of old rats with PVC or ANE and of uterus of old rats with PVC were significantly lower than the corresponding uptakes in the young rats.^ieng