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PubMed2001

Topical application of cyclosporin A induces rapid-remodeling of damaged anagen hair follicles produced in cyclophosphamide administered mice.

Adult C3H mice which had either anagen IV or anagen VI hair follicles were given the anti-tumor drug cyclophosphamide, and cyclosporin A or minoxidil were topically applied to the mice daily from the 4th day after cyclophosphamide administration. In the mice that had anagen IV-hair follicles, 0.5% cyclosporin A induced very thick and long hairs after 21 days of cyclophosphamide administration, while vehicle and 1% minoxidil induced sparsely visible, short hairs. In the mice which received cyclosporin A, the injured hair follicles seemed to remodel themselves into intact anagen hair follicles and restart the production of hairs, instead of shifting to telogen. In the mice that had anagen VI-hair follicles at the time of cyclophosphamide administration, complete alopecia occurred within the first 7 days in all groups. After 14 days of cyclophosphamide administration, hair regrowth was observed in both the 0.5% cyclosporin A-group and the 1% minoxidil- group with the predominant effect over the vehicle. This study shows that anagen hair follicles respond to cyclophosphamide in different ways depending on their stages (IV and VI), and that the damaged anagen IV hair follicles have the potential of remodeling themselves, which is promoted by topical cyclosporin A administration.

Administration, Topical↗

PubMed1998

In vivo prevention of cyclophosphamide-induced Ca2+ dependent damage of rat heart and liver mitochondria by cyclosporin A.

The use of Cyclophosphamide, an anti-cancer and immunosuppressant drug, is accompanied by a number of side effects. Rats injected with a single dose of cyclophosphamide (200 mg kg-1 body weight) showed an increase in the levels of serum glutamate-oxaloacetate transaminase, serum glutamate-pyruvate transaminase, glucose-6-phosphate dehydrogenase and creatine phosphokinase isoenzyme by 53, 24, 55 and 135%, respectively. Also the ability of heart or liver mitochondria to retain accumulated Ca2+ and tetraphenylphosphonium ion was sharply affected in treated rats. Rats injected with the same dose of cyclophosphamide plus cyclosporin A (500 micrograms kg-1 body weight) showed reduction in the levels of those enzymes by about 44, 21, 43 and 57%, respectively compared to cyclophosphamide-treated rats. Cyclosporin A treatment also restored mitochondrial ability to retain accumulated Ca2+ and tetraphenyl phosphonium ions nearly to the level of untreated rats. We suggest that cyclophosphamide induced cardio and hepatotoxicity by increasing heart and liver inner mitochondrial membrane permeability to Ca2+. The protective effect of cyclosporin A against cyclophosphamide-induced damage also support this suggestion.

Alanine Transaminase↗

PubMed1997

Dose-finding study of paclitaxel and cyclophosphamide in advanced breast cancer.

BACKGROUND: The toxicity profile of prolonged infusions of paclitaxel in combination with cyclophosphamide in metastatic breast cancer has already been defined. The objective of this dose-finding study was to determine the maximum tolerable doses (MTDs) of shorter (three-hour) infusions of paclitaxel in combination with i.v. bolus cyclophosphamide in patients who had previously received a maximum of one chemotherapy for advanced breast carcinoma. The MTD of the same regimen with granulocyte colony-stimulating factor (G-CSF) support was then established. PATIENTS AND METHODS: Eighty women with metastatic breast cancer received a total of 352 fully evaluable courses of therapy. The starting doses were paclitaxel 135 mg/m2 and cyclophosphamide 750 mg/m2 given every three weeks. At least three patients were treated at each dose level and if there were dose-limiting toxic effects during the first cycles three additional patients were entered. G-CSF support (5 micrograms/kg s.c.) was added to the second cycle if specific dose-limiting toxicities had occurred during the first cycle. The MTD was defined as the dose level at which more than two of six patients presented dose-limiting toxicities during the first cycle. RESULT: Febrile neutropenia (n = 4) and severe thrombocytopenia (n = 1) defined the MTDs of paclitaxel as 200 mg/ m2 and of cyclophosphamide as 2,000 mg/m2 with or without G-CSF in patients with and, respectively, without prior chemotherapy for advanced disease. Non-hematologic toxicity was moderate. Recommended doses were 200 mg/m2 of paclitaxel and 1,750 mg/m2 of cyclophosphamide with or without G-CSF in patients with and, respectively, without prior chemotherapy. The overall response rate was 25% and 50%, respectively, in patients with and without prior chemotherapy for metastatic disease. Complete remissions (9%) were reported only in patients without prior chemotherapy; antitumour activity in women with anthracycline-resistant disease, with an 8% response rate (95% CI: 1%-26%), was poor. CONCLUSIONS: Paclitaxel at 200 mg/m2 and cyclophosphamide at 1,750 mg/m2 can be safely administered every three weeks to women with advanced breast cancer. The moderate antitumour activity observed with the schedule tested argues against its use as initial therapy for advanced breast cancer.

Adult↗

PubMed1997

Multiple cycles of high-dose doxorubicin and cyclophosphamide with G-CSF mobilized peripheral blood progenitor cell support in patients with metastatic breast cancer.

BACKGROUND: In a previous study we applied doxorubicin and cyclophosphamide in a dose-intensive regimen with GM-CSF to patients with metastatic breast cancer (MBC). That treatment failed to prolong the remission duration compared to conventional-dose chemotherapy. In the present study we escalated the dosages of the same agents to: 1) determine the maximum tolerated dosages (MTD) when given for three cycles with G-CSF mobilised peripheral blood progenitor cell (PBPC) reinfusion and 2) evaluate the antitumour effect of this regimen. PATIENTS AND METHODS: For mobilisation of PBPC, G-CSF 15 microg/kg/day was given subcutaneously (s.c.), and in subsequent cohorts leucapheresis was started on days 3, 4 or 6. The intention was to treat MBC patients with three cycles of doxorubicin and cyclophosphamide at a starting dose of doxorubicin 90 mg/m2 and cyclophosphamide 1000 mg/m2. Dosages were then escalated in subsequent cohorts of at least three patients. In case of dose-limiting mucositis, only the dose of cyclophosphamide was escalated in the next cohort. RESULTS: Twenty-one patients entered this protocol, of which 18 patients received high-dose chemotherapy. The mobilisation of PBPC using G-CSF only was sufficient for three cycles of high-dose chemotherapy in 10 of 21 (47%) patients. Mucositis precluded dose escalation of doxorubicin beyond 110 mg/m2. The MTD in this combination was 110 mg/m2 for doxorubicin, and 4 g/m2 for cyclophosphamide, with haemorrhagic cystitis being the dose-limiting toxicity. The overall response rate was 78% (95% confidence interval (95% CI): 57%-97%), with 22% (95% CI: 3%-41%) complete responses. CONCLUSION: The MTD of this three cycle high-dose regimen was doxorubicin 110 mg/m2 and cyclophosphamide 4 g/m2 with mucositis and cystitis being dose-limiting toxicities. Although the primary aim was not the evaluation of antitumour effect, this high-dose regimen does not appear to provide an improvement of treatment results in comparison with our previous study with the same drugs at moderately high-dosages without stem cell support.

Adult↗

PubMed1995

Changes in solid-state structure of cyclophosphamide monohydrate induced by mechanical treatment and storage.

The effects of mechanical treatment and various storage conditions on the structure of cyclophosphamide monohydrate were evaluated by thermal and X-ray analyses and molecular modeling. The monohydrate form of cyclophosphamide was found to convert to the anhydrous form through a metastable phase. Metastable forms were produced by mechanical treatment and by desiccation. These forms could be detected in differential scanning calometric thermograms as endothermic peaks, at approximately 39 degrees C, and X-ray powder diffractometric analysis, e.g.; by a characteristic reflection at 15.3 degrees (2 theta). Molecular modeling was used to study molecular interactions and putative metastable structures. The dehydration enthalpies of the cyclophosphamide monohydrate obtained from quantum chemical calculations and DSC analysis were 51.6 and 36.1 J/g, respectively. In a unit cell of the stable monohydrate, a water molecule is held by O(7) of the cyclophosphamide molecule and N(6)H of a neighboring cyclophosphamide molecule, with hydrogen bonds enabling existence of a water tunnel. The metastable form of cyclophosphamide is detected when a sterically formed block in the possible tunnel is removed, and the water molecules are allowed to leave the system one by one.

Calorimetry, Differential Scanning↗

PubMedDate not supplied

Fas and Fas ligand immunolocalization in pancreatic islets of NOD mice during spontaneous and cyclophosphamide-accelerated diabetes.

During insulin-dependent diabetes mellitus, immune cells which infiltrate pancreatic islets mediate beta cell destruction over a prolonged asymptomatic prediabetic period. The molecular mechanisms of beta cell death in vivo remain unresolved. At least two major molecular processes of destruction have been proposed. One involves the Fas-FasL (Fas-Fas ligand) system and the other, the perforin pathway. Here, dual-label immunohistochemistry was employed to examine the intra-islet expression, distribution and cellular sources of Fas and FasL in the NOD mouse, during spontaneous diabetes (days 21, 40 and 90) and following acceleration of diabetes with cyclophosphamide (days 0, 4, 7, 11 and 14 after cyclophosphamide administration). The expression of the proteins was correlated with advancing disease. FasL was expressed constitutively in most beta cells but not in glucagon or somatostatin cells or islet inflammatory cells and paralleled the loss of insulin immunolabelling with advancing disease. It was also expressed in beta cells of non-diabetes prone CD-1 and C57BL/6 mice from a young age (day 21). Strong immunolabelling for Fas was first observed in extra-islet macrophages and those close to the islet in NOD and non-diabetes-prone mice. During spontaneous and cyclophosphamide diabetes, it was observed in a higher proportion of islet infiltrating macrophages than CD4 and CD8 T cells, concomitant with advancing insulitis. In cyclophosphamide-treated mice, the proportion of Fas-positive intra-islet CD4 and CD8 T cells at day 14 (with and without diabetes) was considerably higher than at days 0, 4, 7 and 11. At days 11 and 14, a proportion of Fas-positive intra-islet macrophages co-expressed interleukin-1beta and inducible nitric oxide synthase. Fas was not detectable in beta cells and other islet endocrine cells during spontaneous and cyclophosphamide induced diabetes. Our results show constitutive expression of FasL in beta cells in the NOD mouse and predominant expression of Fas in intra-islet macrophages and to a lesser extent in T cells prior to diabetes onset. Interleukin-1beta in intra-islet macrophages may induce Fas and inducible nitric oxide synthase expression in an autocrine and paracrine manner and mediate beta cell destruction or even death of some macrophages and T cells. However, other mechanisms of beta cell destruction during spontaneous and cyclophosphamide-accelerated diabetes and independent of Fas-FasL, require examination.

Animals↗

PubMed2004

Effects of T-activin and vitamin E on toxicity and antitumor activity of cyclophosphamide.

We studied the effect of combination treatment with T-activin and vitamin E on acute toxicity and antitumor activity of cyclophosphamide in mice. Combined administration of these preparations 1.37-fold increased the maximum permissible dose of cyclophosphamide without affecting its LD(50)and delayed mouse death from cyclophosphamide toxicity. Most mice died only 3 days after combination treatment with the test preparations and cyclophosphamide in doses of LD(16)-LD(84). The second peak of death from hematologic toxicity of cyclophosphamide was absent under these conditions. T-activin and vitamin E did not abolish the antitumor effect of cyclophosphamide on mice with subcutaneously implanted P-388 lympholeukemia. Tumor growth was suppressed by 100%.

Animals↗

PubMed1994

Enhancement of cyclophosphamide cytotoxicity in vivo by the benzamide analogue pyrazinamide.

The ability of pyrazinamide to enhance the in vivo cytotoxicity of cyclophosphamide in Lewis lung and RIF-1 tumours was investigated. Using an in vivo/in vitro excision assay a large single dose of pyrazinamide (500 mg kg-1 i.p.) was shown to enhance the tumour cell killing by cyclophosphamide. This enhancement was greatest when pyrazinamide was administered before the alkylating agent and had a dose-modifying effect on all cyclophosphamide doses tested, giving rise to a mean (+/- 1 s.e.) enhancement ratio (ER) of 1.54 (+/- 0.15) for the Lewis lung and 1.24 (+/- 0.08) for the RIF-1 tumour. Pyrazinamide also increased the cytotoxic action of cyclophosphamide in a normal tissue, namely white blood cell counts. However, the ER was only 1.14 (+/- 0.08), which although not significantly different from the value seen in RIF-1 was significantly less than the ER obtained with Lewis lung, suggesting the possibility of a therapeutic gain. This benzamide analogue did not appear to inhibit recovery from cyclophosphamide-induced potentially lethal damage in tumours, nor did it alter the bioactivation of cyclophosphamide or the subsequent clearance of the cytotoxic species from the plasma, so the mechanism for this chemosensitisation remains unclear.

Animals↗

PubMed1988

Rapid development of enhanced clearance after high-dose cyclophosphamide.

We have studied the disposition of cyclophosphamide, its major cytotoxic metabolite phosphoramide mustard, and the synthetic glucocorticoid dexamethasone in nine patients receiving high-dose cyclophosphamide daily for 2 days before bone marrow transplantation. The total body clearance of cyclophosphamide was observed to increase from 93 +/- 27 ml/min on the first day to 178 +/- 83 ml/min on the second day. This was associated with an increase in the clearance of dexamethasone from 369 +/- 104 ml/min to 526 +/- 123 ml/min. An increased rate of formation of phosphoramide mustard with higher peak concentrations was also seen. Simulation studies show that these changes are most likely the result of an increase in the hepatic metabolism of cyclophosphamide. These results show that high-dose cyclophosphamide causes an increase in its own clearance and that of dexamethasone through an apparent induction of hepatic-metabolizing enzymes detectable 24 hours after initial exposure to cyclophosphamide.

Adult↗

PubMed2002

A phase I/II study of 4 monthly courses of high-dose cyclophosphamide and thiotepa for metastatic breast cancer patients.

This pilot phase I/II study intended to determine the maximum tolerated dose of cyclophosphamide and thiotepa administered on four consecutive courses with peripheral blood progenitor cell and granulocyte-colony stimulating factor support, as first-line therapy for hormone-refractory metastatic breast cancer patients. Twenty-eight patients were entered in the study. After two courses of epirubicin (120 mg m(-2)) and cyclophosphamide (2 g m(-2)) followed by granulocyte-colony stimulating factor injection and leukaphereses, patients received four cycles of cyclophosphamide and thiotepa. Each cycle was followed by peripheral blood progenitor cell and granulocyte-colony stimulating factor supports, then repeated every 28 to 35 days. Six escalating dose levels of cyclophosphamide and thiotepa were planned, beginning at cyclophosphamide 1.5 g m(-2) and thiotepa 200 mg m(-2). At least three patients were enrolled for each dose level. Eighteen patients completed the study. The maximum tolerated dose was 3000 mg m(-2) cyclophosphamide and 400 mg m(-2) thiotepa per course. Haematological toxicity was manageable on an outpatient basis and did not increase significantly with dose escalation. Dose-limiting toxicity was chemotherapy-induced immunosuppression, which resulted in one toxic death and two life-threatening infections. Median times to treatment failure and survival were 11 and 26 months, respectively. Three patients were alive, free of disease 30 months after completion of the study. Such therapy allows for high-dose intensity and high cumulative doses on a short period of time with manageable toxicity.

Adult↗

PubMed2006

Cyclophosphamide versus placebo in scleroderma lung disease.

BACKGROUND: We conducted a double-blind, randomized, placebo-controlled trial to determine the effects of oral cyclophosphamide on lung function and health-related symptoms in patients with evidence of active alveolitis and scleroderma-related interstitial lung disease. METHODS: At 13 clinical centers throughout the United States, we enrolled 158 patients with scleroderma, restrictive lung physiology, dyspnea, and evidence of inflammatory interstitial lung disease on examination of bronchoalveolar-lavage fluid, thoracic high-resolution computed tomography, or both. Patients received oral cyclophosphamide (< or =2 mg per kilogram of body weight per day) or matching placebo for one year and were followed for an additional year. Pulmonary function was assessed every three months during the first year, and the primary end point was the forced vital capacity (FVC, expressed as a percentage of the predicted value) at 12 months, after adjustment for the baseline FVC. RESULTS: Of 158 patients, 145 completed at least six months of treatment and were included in the analysis. The mean absolute difference in adjusted 12-month FVC percent predicted between the cyclophosphamide and placebo groups was 2.53 percent (95 percent confidence interval, 0.28 to 4.79 percent), favoring cyclophosphamide (P<0.03). There were also treatment-related differences in physiological and symptom outcomes, and the difference in FVC was maintained at 24 months. There was a greater frequency of adverse events in the cyclophosphamide group, but the difference between the two groups in the number of serious adverse events was not significant. CONCLUSIONS: One year of oral cyclophosphamide in patients with symptomatic scleroderma-related interstitial lung disease had a significant but modest beneficial effect on lung function, dyspnea, thickening of the skin, and the health-related quality of life. The effects on lung function were maintained through the 24 months of the study.

Administration, Oral↗

PubMed2002

Effects of cyclophosphamide on the femoral epiphyseal growth plate in young Sprague-Dawley rats.

The purpose of this study was to assess the effects of cyclophosphamide on cartilaginous growth and differentiation. Cyclophosphamide is a drug commonly used in the treatment of neoplastic diseases and in preparation for bone marrow transplantation. Eighteen Sprague-Dawley rats divided into control and experimental groups received 2 i.p. injections of either saline or cyclophosphamide (30 mg/kg) with a 3-day interval starting from day 10 after birth. Effects on the proximal femoral epiphyses were evaluated histomorphometrically as well as semi-quantitatively at day 31 after birth. Results showed a significant reduction in length of the cyclophosphamide-treated femora compared to the controls. This could be attributed to a significant reduction in the thickness of the growth zone. Cell differentiation throughout the growth plates was clearly disturbed, involving nesting of cells, loss of polarity, and impaired maturation as seen by areas of excessive hyalinization. Although the effects of cyclophosphamide on the growth plates were significant compared to controls, the changes were not as extensive as previous reports have indicated. This could be attributed primarily to the fact that a comparatively low dose of the drug was used in the present study. Also, a period of recovery was allowed prior to evaluation. Nevertheless, significant effects remained which should be considered when treating young children with cyclophosphamide.

Animals↗

PubMed1967

Studies on cyclophosphamide-induced tolerance to sheep erythrocytes.

Complete immunological tolerance to sheep cells can be induced in mice when cyclophosphamide is injected together with sheep cells or up to 72 hr before or 48 hr after the antigen. As is true for radiation-induced immune suppression, the drug is most effective when given in the 24 hr prior to antigen. Complete cyclophosphamide-induced immunological suppression requires large doses of sheep cells (6.2 x 10(9) cells), presumably to enable antigen to reach sequestered receptor sites. The cyclophosphamide tolerance system has been analyzed with the Jerne technique to determine plaque-forming cells and with isotopic methods to measure rates of nucleic acid synthesis. This drug suppression has been found to consist of two components. The first is nonspecific injury to the lymphoid system caused by the cytotoxic drug and is related to the proportion of spleen cells killed. The second is antigen-specific immunological tolerance and appears to correlate with profound depression of deoxyribonucleic acid synthesis in the surviving cells. This tolerance is thought to be most consistent with a mechanism in which antigenic stimulation in the presence of cyclophosphamide-inhibited DNA synthesis and mitosis leads to the elimination or death of the specific immunological clone. Tolerance induction with cyclophosphamide is associated with loss of the 19S hemolysin plaques which are seen in nonstimulated mouse spleen, implicating these cells in immune responsiveness. The ability to induce tolerance is lost on the 3rd postantigen day at the end of a 24-hr period in which 19S cells have increased 8-fold and 7S cells 200-fold. The data suggest that loss of sensitivity is due to the emergence on day 3 of drug-resistant plaque-forming cells, particularly those of the 19S variety. In the succeeding days after antigen injection there is a progressive increase in the resistance of plaque-forming cells to cyclophosphamide administration.

Animals↗

PubMed1982

Cyclophosphamide-facilitated adoptive immunotherapy of an established tumor depends on elimination of tumor-induced suppressor T cells.

On the basis of preceding studies showing that tumor-induced, T cell-mediated immunosuppression serves as an obstacle to adoptive immunotherapy of the Meth A fibrosarcoma, it was predicted that cyclophosphamide treatment of tumor bearers would remove this obstacle and allow passively transferred immune T cells to cause tumor regression. It was found that infusion of immune spleen cells alone had no effect on tumor growth, and cyclophosphamide alone caused a temporary halt in tumor progression. In contrast, combination therapy consisting of intravenous injection of 100 mg/kg of cyclophosphamide followed 1 h later by intravenous infusion of tumor-immune spleen cells caused small, as well as large tumors, to completely and permanently regress. Tumor regression caused by combination therapy was completely inhibited by intravenous infusion of splenic T cells from donors with established tumors, but not by spleen cells from normal donors. These suppressor T cells were eliminated from the spleen by treating the tumor-bearing donors with 100 mg/kg of cyclophosphamide. Immune T cells, in contrast, were resistant to this dose of cyclophosphamide. These results show that failure of intravenously-infused, tumor-sensitized T cells to cause regression of the Meth A fibrosarcoma growing in its syngeneic or semi-syngeneic host is caused by the presence of a tumor-induced population of cyclophosphamide-sensitive suppressor T cells.

Animals↗

PubMed2004

Occupational dermal exposure to cyclophosphamide in Dutch hospitals: a pilot study.

INTRODUCTION: Several studies have shown that exposure to antineoplastic drugs can cause reproductive toxic effects as well as carcinogenic effects. Presence of these drugs in the urine of hospital personnel has been widely studied and some work has been done on exposure by inhalation. So far, assessment of dermal exposure to antineoplastic drugs has not been extensively studied. In this pilot study we assessed potential and actual dermal exposure for several common hospital tasks. Results were used to derive an optimal measurement strategy for a currently ongoing exposure survey. METHODS: Dermal exposure to cyclophosphamide was determined in three Dutch hospitals during five tasks (preparation, decanting urine, washing the patient, removing bed sheets and cleaning the toilet) using pad samples on 10 body locations. In addition, protective medical gloves (worn during the performance of these activities) were collected to estimate potential exposure of the hands. Subsequently, hands were washed to measure actual exposure of the hands. Bulk samples (i.e. application and body fluids) were collected and possible contact surfaces were monitored to assess the amount of cyclophosphamide potentially available for exposure. RESULTS: The results show that hospital personnel (i.e. pharmacy technicians and oncology nurses) are dermally exposed to cyclophosphamide during performance of their daily duties. Exposure occurred predominantly on the hands and sporadically on other body locations (i.e. forehead and forearms). Gloves used during preparation of cyclophosphamide were more contaminated than gloves used in other tasks, however, actual exposure of the hands (underneath the gloves) was highest during decanting of urine of treated patients. Glove samples correlated significantly with handwash samples (r = 0.57, P = 0.03, n = 15). The level of protection from gloves varied between tasks, being highest for gloves used during preparation (median = 98%) and lowest for gloves used during decanting urine (median = 19%). CONCLUSION: This pilot study demonstrated that dermal exposure to cyclophosphamide is common among hospital personnel. The results showed that hands, forearms and forehead accounted for 87% of the cyclophosphamide total body exposure. Glove samples together with handwash samples enabled estimation of glove efficiency, which appeared to vary strongly between tasks observed.

Antineoplastic Agents, Alkylating↗

PubMed2001

Administration of cyclophosphamide at different stages of follicular maturation in mice: effects on reproductive performance and fetal malformations.

This study assessed reproductive performance, fetal viability and teratogenicity in female mice exposed to cyclophosphamide across a timeline corresponding to different stages of follicle maturation. Pregnancies were established in female Balb/c mice 1-4 weeks after administration of a non-sterilizing dose of cyclophosphamide (75 mg/kg). Each mating group represented a different stage of follicular growth at the time of cyclophosphamide exposure. The number of corpora lutea, pregnancies and fetal resorptions were determined. Surviving fetuses were evaluated for gross malformations. Results indicated that conceptions attributable to follicles exposed to cyclophosphamide at a mature stage had a significantly lower number of implantation sites, 4.82 +/- 1.01 versus 8.27 +/- 0.81 in controls (P = 0.001) and a high resorption rate, 56% +/- 0.11 versus 34% +/- 0.07 in controls (P = 0.05). The proportion of corpora lutea in this group which resulted in viable fetuses was extremely low, 0.2 +/- 0.06 versus 0.51 +/- 0.07 in controls (P = 0.001). Malformation rate was more than 10 times higher in all treated groups (P < 0.05) and a particularly high incidence of 33% (P = 0.0014) was observed in conceptions attributable to oocytes exposed to cyclophosphamide at the earliest stages of follicle growth. With an extended interval between exposure and mating the malformation rate gradually decreased towards normal values in the 12th week group. This study suggests that the effect of cyclophosphamide on female gametes and subsequently on future reproduction is influenced by the stage of oocyte maturation at the time of exposure. Early fertilization post-chemotherapy can result in a high rate of pregnancy failure and high malformation rate. This should be taken into account when considering the use of oocyte retrieval, IVF and embryo cryopreservation in patients currently undergoing chemotherapy.

Abnormalities, Multiple↗

PubMed2003

Numerical chromosomal abnormalities in rat epididymal spermatozoa following chronic cyclophosphamide exposure.

Chronic, low-dose treatment of male rats with cyclophosphamide, a chemotherapeutic agent, is known to affect progeny outcome adversely in a dose-dependent and time-specific manner, resulting in increased pre- and postimplantation loss as well as malformations. Concern exists regarding the genetic quality of mature gametes exposed to cyclophosphamide during mitosis and meiosis. The goal of the present study was to determine the effect of chronic cyclophosphamide treatment during spermatogenesis on the frequency of numerical chromosomal anomalies in epididymal spermatozoa. Male rats were treated with either saline or cyclophosphamide (6 mg kg-1 day-1) for 6 or 9 wk, and cauda epididymal spermatozoa were collected. The rat sperm Y-4 fluorescence in situ hybridization assay was used to assess the induction of spermatozoal disomy, nullisomy, and diploidy involving chromosomes Y and 4. The overall frequency of numerically abnormal spermatozoa was elevated approximately 2-fold (P < 0.001) after 9 wk of cyclophosphamide treatment. Exposure for 9 wk, but not for 6 wk, significantly increased the frequency of spermatozoa with chromosome 4 disomy (P < 0.02) and nullisomy (P < 0.05), but disomy Y and diploidy were not significantly increased with treatment compared to corresponding controls. Independent of treatment, only 27% of aneuploid spermatozoa presented with morphological abnormalities, but all diploid spermatozoa were approximately twice the size of normal cells. Thus, cyclophosphamide disrupts meiotic events before pachynema during spermatogenesis, emphasizing the potential for adverse progeny outcomes following genotoxic damage.

Animals↗

PubMed1992

Adverse effects of cyclophosphamide on progeny outcome can be mediated through post-testicular mechanisms in the rat.

Previous studies from our laboratory have suggested that, in addition to an effect on spermatozoa in the testis, cyclophosphamide may have an adverse effect on spermatozoa after they leave the testis, during epididymal transit. To elaborate on this post-testicular effect on germ cells and to determine at which site(s) in the epididymis germ cells are most sensitive to cyclophosphamide treatment, three experiments were undertaken. First, the time course of the effect of treatment of male rats with cyclophosphamide on the outcome of their progeny was determined. Male rats were treated daily by gavage with saline or one of two doses of cyclophosphamide (6.8 mg/kg or 10.0 mg/kg) for 1, 4, or 7 days. At the end of each treatment period, males were mated to assess the effect on pregnancy outcome. No effect was observed on pre-implantation loss at any time among any of the groups, but there was a time-dependent and dose-related increase in post-implantation loss. Post-implantation loss was significantly increased after 4 days of treatment and reached nearly 40% after 7 days of drug exposure (10.0 mg/kg). Second, the effect of treatment with single high doses of cyclophosphamide was studied. Male rats were treated with a single dose of cyclophosphamide (10, 30, or 70 mg/kg) and bred 1 day and 4 days post-treatment. No significant change in pre-implantation loss was observed at either time point; no change in post-implantation loss was found after 1 day post-treatment. However, a significant increase in post-implantation loss was observed in the two high-dose groups 4 days post-treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗