Uterine Cervix In Mice Research Articles

Estrogen and hypoxia regulate expression of vascular endothelial growth factor and its receptors in uterine cervix of mice, which are localized in multiple cells of the tissue in mice and human

We have previously demonstrated the existence and profile of VEGF and its receptors, Flt‐1 and KDR, in the uterine cervix of rodents and deciphered the genome‐wide genes it regulates; and more recently examined some of VEGF's roles in uterine cervical remodeling. In the present study, we examined the effects of hypoxia and estrogen on the expression pattern of VEGF and its receptors, and mapped their cellular expression in the uterine cervix of mice and human. Ovariectomized mice were treated dose‐dependently with either 17β‐estradiol (E2) or cobalt chloride (CoCl2), to mimic hypoxia. Both human and mice sections were stained with H&E and protein expression of VEGF and its receptors were performed using confocal immunofluorescence. Also, mice tissues were analyzed for gene and protein expressions using real time PCR and Western blot, respectively. VEGF and its receptors were localized in epithelial and stromal cells in both species. VEGF and Flt‐1 expression were up‐regulated dose dependently by E2, while KDR was down‐regulated (p<0.05). VEGF and KDR were up‐regulated by 30 minutes post CoCl2 treatment, while Flt‐1 was up‐regulated at 1h post treatment. We conclude that VEGF and its receptors are present and variably expressed in the uterine cervix of women and mice; their expression in mice is altered by hypoxia and estrogen dose‐dependently. Funding: Office of students Research, Appalachian State.

Profile of hypoxia inducible factor 1 alpha [HIF‐1a], vascular endothelial growth factor [VEGF], and its receptors in the postpartum uterine cervix of mice

The uterine cervix undergoes pronounced changes prior to term (pre‐partum) for a timely passage of the fetus, and also marked changes immediately after term or birth (post‐partum=pp) to enhance tissue repair in order to restore the tissue to its nonpregnant state. Because the vasculature plays a vital role in wound repair, it likely plays a similar function in pp uterine cervical repair, and since vascular endothelial growth factor (VEGF) is the key architect of vascular events and hypoxia‐inducible factor 1α (HIF‐1α) is the most potent transcription factor of VEGF, we examined the profile of HIF‐1α, VEGF, and VEGF receptors in the pp uterine cervix using timed‐pregnant (day 10) mice (C57BL6/129SvEv) allowed to undergo normal gestation and labor. Tissues (n=3) were harvested at an interval of 8hr, beginning with the emergence of the first pup (0hrs pp) to 48hrs pp, and analyzed for presence and quantity of HIF1‐α and VEGF and its receptors, Flt‐1 & KDR, using qRT‐PCR, Western blot and immunofluorescence. All molecules were found to be readily expressed during the initial part of pp, but declined by 2 days pp, relative to 0hrs pp. We conclude that HIF‐1α, VEGF, Flt‐1 and KDR likely play crucial roles in the wound healing of the pp uterine cervix. Studies to elucidate the potential mechanism underlying the actions of these molecules are ongoing.Funding: Office of Student Research, Appalachian State University.

Vascular endothelial growth factor induces mRNA expression of pro-inflammatory factors in the uterine cervix of mice

Inflammation is believed to play a role in uterine cervical remodeling and infection-induced preterm labor. One of the distinct features of remodeling uterine cervix is presence of prominent vascular events, such as angiogenesis, vasodilation, and vascular permeability. Although the functional significance of these features is not yet clear, we know that in most tissue types, vascular remodeling is intricately intertwined with inflammation. Since vascular endothelial growth factor (VEGF) is the major architect of vascular remodeling, we sought to examine and elucidate the potential relationship between VEGF and inflammation in the uterine cervix of non-pregnant mice. The animals used were divided into 4 treatment groups: A) negative control (vehicle only), B) positive control (lipopolysaccharide, LPS), C) recombinant VEGF-164 protein, and D) LPS + VEGF blocker (n = 3). After the appropriate treatments, the uterine cervices were harvested and analyzed using real-time PCR and confocal fluorescence microscopy. Results showed that exogenous VEGF upregulates expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α mRNAs, whereas VEGF blocker partially diminishes the LPS-induced expression of pro-inflammatory factors compared to the positive control group. We conclude that a positive feed-forward relationship likely exists between VEGF and inflammation in the uterine cervix, thus implicating VEGF in inflammation-induced preterm labor.

Influence of alpha tocopherol during carcinogenesis in uterine cervix of mice

The effect of supplemental alpha tocopherol and its mode of action were evaluated during carcinogenesis in uterine cervix of mice by chronic exposure to 20-methylcholanthrene (MC). Oral administration of alpha tocopherol restricted the progression of dysplastic changes in cervix uteri which lead to carcinoma in situ during chronic exposure to MC. Enhanced mitogenic stimulation of peripheral blood lymphocytes (PBL) indicating improved immune response was also noted following treatment. A decrease in micronucleus frequency in the vaginal exfoliated cells suggested reduced genotoxic effect of the carcinogen after alpha tocopherol administration. A decrease in lipid peroxides following ingestion of alpha tocopherol imply its protective role on DNA damage by oxidative free radicals. Similarly, elevated glutathione level and increased activities of glutathione-S-transferase, glutathione peroxidase, catalase and superoxide dismutase indicated involvement of alpha tocopherol in host's detoxification system.

Influence of ascorbic acid on MCA-induced carcinogenesis in the uterine cervix of mice

The present study evaluates the possible modulatory influence of ascorbic acid (AA) on (methylcholanthrene) MCA-induced cervical carcinogenesis in mice. Ascorbic acid was given daily for different durations in drinking water at the dose level of 2 mg/ml. In animals that received no modulator, placement of cotton threads impregnated with beeswax containing ∼600 μg of MCA for 16 weeks yielded 76.1% carcinomas in the uterine cervix. Administration of AA for the entire period of 16 weeks resulted in the reduction of MCA-induced cervical carcinomas to 33.3%. AA was capable of reducing cervical cancer incidence to 33.3% even when it was given for only 6 weeks following MCA-thread insertion into the uterine cervix. However, when it was given for a period of 10 weeks after 6 weeks of MCA-thread insertion the carcinoma incidence was as high as 66.6%. Results of the present study demonstrate that AA, especially when given during the initiational phase, significantly inhibits MCA-induced cervical carcinogenesis in mice.

Modulatory influence of oral contraceptive pills Ovral and Noracycline on 3-methylcholanthrene-induced carcinogenesis in the uterine cervix of mouse.

The present study reports the modulatory influences of combined oral contraceptive formulations, Ovral (0.05 mg ethinylestradiol plus 0.5 mg norgestrel per pill) and Noracycline (0.05 mg ethinylestradiol plus 0.1 mg lynestrenol per pill), on methylcholanthrene (MCA)‐induced carcinogenesis in the uterine cervix of Swiss albino mouse. Placement of cotton thread impregnated with beeswax containing ∼ 300 μg of MCA yielded cervical tumors in 0.0%, 8.6% and 26% animals, respectively, in 30, 60 and 90 days. Concomitant treatments with doses D1 (1/2000th of a pill), D2 (1/ 200th of a pill) and D3 (1/20th of a pill) of Ovral yielded cervical tumors in 0.0%, 0.0% and 4.5% mice at 30 days, 0.0%, 6.2% and 10% mice at 60 days and in 3.3% (P<0.05), 3.4% (P<0.05) and 47% mice at 90 days, respectively. Likewise, concomitant treatments with doses D1 (1/2000th of a pill), D2 (1/200th of a pill) and D3 (1/20th of a pill) of Noracycline yielded cervical tumors in 0.0%, 0.0%, 16.6% mice at 30 days, 4%, 3.7% and 54% (P<0.05) mice at 60 days and 3.2% (P<0.05), 20% and 63% (P<0.05) of mice at 90 days, respectively. Both Ovral and Noracycline displayed biphasic action on MCA‐induced cervical carcinogenesis in mice. At lower dose levels (D1 and D2), they were inhibitory while at the higher dose level (D3) they were augmentatory in their actions. Both pills also significantly enhanced the incidence of cervical hyperplasia.

Modulatory influence of injectable contraceptive steroid medroxyprogesterone acetate on methylcholanthrene-induced carcinogenesis in the uterine cervix of mouse.

Methylcholanthrene (approximately 300 micrograms) plus beeswax-impregnated thread, when placed inside the canal of the uterine cervix of virgin female adult mice for 30, 60 and 90 days produced cervical tumors in 0.0, 10 and 30% of mice, respectively. Employing this experimental cervical carcinogenesis model system, the present study evaluated the modulatory influence of medroxyprogesterone acetate (MPA) on the incidences of precancerous and cancerous lesions in the cervical epithelium as well as on phase I and phase II drug metabolizing enzymes and acid soluble sulfhydryl level in the liver. Intramuscular administration of MPA (50 micrograms every 5th day) to the carcinogen-thread inserted mice for 30, 60 and 90 days produced cervical tumors respectively in 0.0, 13.3 and 60.5% (P less than 0.05) of mice. A significant increase (P less than 0.05) in hyperplasia was also observed in the present study. A significant decrease in cytochrome b5 was found after 30 days.

Chemopreventive action of selenium on methylcholanthrene-induced carcinogenesis in the uterine cervix of mouse.

The placement of cotton thread impregnated with beeswax containing methylcholanthrene (MCA, approximately 600 micrograms) inside the canal of the uterine cervix of virgin, adult mice results in the emergence of precancerous and cancerous lesions in the cervical epithelium. Employing this experimental carcinogenesis model system, the present study evaluates the chemopreventive action of selenium on the incidences of precancerous and cancerous lesions in the cervical epithelium. When selenium was administered through drinking water at the dose level of 1 ppm for 1 week before and 12 weeks following carcinogen thread insertion, the cervical carcinoma incidence, as compared to that in control mice (72%), was 37%. This decline in the incidence of carcinoma was significant (p less than 0.05). The incidences of hyperplasia and dysplasia show a decreasing trend with selenium treatment in MCA-thread-inserted animals.

Chemopreventive action of mace ( Myristica fragrans, Houtt) on methylcholanthrene-induced carcinogenesis in the uterine cervix in mice

The present paper reports the chemopreventive action of mace (aril covering the testa of the seed of Myristica fragrans) on 3-methylcholanthrene (MCA)-induced carcinogenesis in the uterine cervix of virgin, young adult, Swiss albino mice. Placement of cotton-thread impregnated with beeswax containing MCA (∼ 600 μg) inside the canal of the uterine cervix results in the appearance of precancerous and cancerous lesions in the cervical epithelium. In this experiment using the cervical carcinogenesis model system, if mace was administered orally at the dose level of 10 mg/mouse per day for 7 days before and 90 days following carcinogen thread insertion, the cervical carcinoma incidence, as compared with that of the control (73.9%), was 21.4%. This decline in the incidence of carcinoma was highly significant (P < 0.001). The incidence of precancerous lesions did not display any definite association with different treatments.

Chemopreventive action of garlic on methylcholanthrene-induced carcinogenesis in the uterine cervix of mice

The present paper reports the chemopreventive action of garlic on 3-methylcholanthrene (MCA)-induced carcinogenesis in the uterine cervix of virgin young adult Swiss albino mice. Insertion of sterile cotton thread impregnated with beeswax containing ∼600 μg of MCA inside the canal of uterine cervix results in the appearance of precancerous and cancerous lesions in the cervical epithelium. In this experimental cervical carcinogenesis model system, if garlic was administered orally at the dose level of 400 mg/kg body wt./day for 2 weeks before and 4 weeks following carcinogen thread insertion. The cervical carcinoma incidence, as compared with that of the positive control (73%), was 23%. This decline in the incidence of carcinoma was highly significant (P < 0.01). Hyperplastic and dysplastic changes did not show any definite correlation with the garlic treatment.

Inhibitory action of dehydroepiandrosterone on methylcholanthrene-induced carcinogenesis in the uterine cervix of mouse

The present paper reports the chemopreventive action of Dehydroepiandrosterone (DHEA) on Methylcholanthrene- (MCA) induced carcinogenesis in the uterine cervices of adult virgin Swiss albino mice. Placement of sterile double cotton thread impregnated with beeswax containing 600 μg of MCA in the cervical canal produced tumors in 85.7% of mice in 16 weeks. When such carcinogen-containing threads were inserted into the uterine cervices of mice that were being fed on diets of 0.025%, 0.05% and 0.1% DHEA for a period of two preinsertion and sixteen postinsertion weeks, the cervical tumor incidences were reduced to 59.0%, 34.7% (P < 0.01) and 14.2% (P < 0.01), respectively. It is inferred that DHEA inhibits MCA-induced cervical carcinogenesis and the inhibitory action is dependent upon the dose of the drug.

Modulatory influences of exogenous estrogen on MCA-induced carcinogenesis in the uterine cervix of mouse

Placement of cotton-thread impregnated with beeswax containing methylcholanthrene (approx. 600 μg) inside the canal of uterine cervix of virgin adult mice results in the emergence of precancerous and cancerous lesions in the cervical epithelium. Employing this experimental cervical carcinogenesis model system, the present study evaluates the modulatory influence of exogenous 17β-estradiol on the incidences of precancerous and cancerous lesions in the cervical epithelium. When 17β-estradiol was administered weekly at the dose levels of 0.01 μg, 0.1 μg, 5 μg and 50 μg for 16 weeks following carcinogen-thread insertion, the cervical carcinoma incidences, as compared to that in positive control mice (76.1%), were 66.6%, 61.5%, 55.5% and 42.1%, respectively. The decline in the incidence of carcinomas at 50 μg/week dose level was significant (P < 0.05). Hyperplastic and dysplastic changes did not show any definite correlation with the various treatments.

Experimental studies of carcinogenesis of the uterine cervix in mice

In conclusion, the histogenesis of cervical carcinomas induced in mice by coaltar hydrocarbons or inactivated herpes simplex virus, types 1 and 2, has been described. The lesions antedating the development of squamous cell carcinoma were similar to lesions encountered in patients with the same keratinizing type of carcinoma of the ectocervix. A theory for the development of the three grades of human cervical squamous cell carcinoma has been presented based on experimental and clinical data which demonstrate that each of the three grades of cancer consists of cells which resemble those of the tissue of origin and of the antecedent noninvasive lesion.

The basement membrane in experimentally induced atypias and carcinoma of the uterine cervix in mice

Basement membrane-specific antigens of the squamous epithelium of the uterine cervix were investigated in 19 normal mice, in 7 mice with cervical atypia and in 3 mice with invasive carcinoma. Cervical atypia and carcinoma were induced by local application of benzo(a)pyrene. Basement membrane-specific antigens were demonstrated by immunofluorescence with sera from patients with bullous pemphigoid. Both normal squamous cervical epithelium and atypical cervical epithelium showed the presence of a continuous, clearly delineated basement membrane. Clusters of invasive squamous carcinoma were also surrounded by a fluorescent basement membrane which, however, appear fragmented or discontinuous. The results suggest that the ability of cervical squamous cells to secrete basement membrane antigens is not completely lost during carcinogenesis, thus substantiating our previous observations in the cervix of human subjects.

Carcinogenesis With 3-Methylcholanthrene in Uterine Cervix of Mice Treated Neonatally With Estrogen&lt;xref ref-type="fn" rid="FN1"&gt;2&lt;/xref&gt;

Carcinogenesis With 3-Methylcholanthrene in Uterine Cervix of Mice Treated Neonatally With Estrogen&lt;xref ref-type="fn" rid="FN1"&gt;2&lt;/xref&gt;

Cancer of the Uterine Cervix in Mice Fed a Liquid Diet Containing an Antifertility Drug

Enovid was administered to BALB/c mice in a liquid Metrecal diet. Experimental animals developed uterine cervical and vaginal lesions while the control groups did not develop uterine cervical or vaginal carcinomas. The experimental techniques of introducing material in a liquid Metrecal diet has many applications including the answering of some questions on dosage of estrogens and limitations of exposure time.

Carcinogenesis of the Uterine Cervix in Mice: Effect of Castration After Limited Application of 3-Methylcholanthrene&lt;xref ref-type="fn" rid="FN2"&gt;2&lt;/xref&gt;

Carcinogenesis of the Uterine Cervix in Mice: Effect of Castration After Limited Application of 3-Methylcholanthrene&lt;xref ref-type="fn" rid="FN2"&gt;2&lt;/xref&gt;

Carcinogenicity of benzo(a) anthracene and benz(c)phenanthrene derivatives.

Abstract The carcinogenic effect of all monomethyl derivatives of benz(a)anthracene and some monomethyl derivatives of benzo(c)phenanthrene was studied in mice. The compounds were applied cutaneously by painting and subcutaneously by injection in solution. The toxic and carcinogenic effects of four fluoro-substituted and three methyl-substituted benz (a) anthracenes were studied when these compounds had been adsorbed to strings inserted into the uterine cervix of mice. The neoplasia-inducing potential as a function of certain chemical groups at various sites on the benz (a)-anthracene molecule is presented. The extreme toxicity of 4-fluoro-7-methyl benz(a)anthracene prohibited its use in this experiment.

Carcinogenesis of the Uterine Cervix in Mice: Effect of Diethylstilbestrol After Limited Application of 3-Methylcholanthrene&lt;xref ref-type="fn" rid="FN1"&gt;2&lt;/xref&gt;

Interrelationships between a chemical carcinogen and hormonal status in cervical carcinogenesis were investigated. No significant effects of castration or added estrogen stimulation were detected under conditions of prolonged exposure to methylcholanthrene by cervical painting or continuous exposure of the endocervical epithelium to a methylcholanthrene-coated thread. When the time of exposure to methylcholanthrene-coated threads was reduced to 4 weeks a low incidence of cervical carcinoma appeared in castrates providing a baseline for determination of the effect of subsequent systemic treatment with estrogenic hormone. The incidence of cervical carcinoma was increased and the average laten period decreased in strains A/Sn C3HeB/FeJ and 129/J when systemic treatment with diethylstilbestrol (DES) followed a 4-week exposure of the castrate endocervical epithelium to a methylcholanthrene-coated thread. The incidence of carcinoma increased from 13.2-90.2% when 33% DES-cholesterol pellets were administered. The average latent period was reduced from 12.3-6.7 months. 10% DES-cholesterol pellets increased the incidence of carcinoma from from 3.3-19.1% with lesser shortening of the average latent period. Plain-thread stimulation of the castrate endocervical epithelium for 4 weeks followed by 33% DES pellets produced an incidence of 7.1% carcinoma in the 3 strains. 10% DES pellets produced carcinoma in 1.5% of strain A castrates. Plain-thread stimulation for 4 weeks produced no carcinomas among 78 mice. The promoting action of estrogen in these experiments is discussed. (authors)

Unusual Neoplastic Lesions of the Uterine Horns of Estrogen-Treated Mice&lt;xref ref-type="fn" rid="fn1"&gt;2&lt;/xref&gt;

The effect of estrogens administered either parenterally or topically on cancer of the vagina and uterine cervix in mice from the BC stock was studied. Mice were exposed to estrogens for 112 to over 300 days. 2 mice received weekly injections of 250 mcg stilbestrol 5 received weekly injections of 16.6 mcg of estradiol benzoate and 1 had a pellet of stilbestrol and cholesterol fixed in the upper vagina (1:3). All 8 of the mice had subserosal uterine lesions adenomas or adenocarcinomas. 5 of the mice had infiltrative uterocervical lesions as well 2 of which were considered to be epidermoid carcinomas. The majority of the tumors were found at or near the uteromesometrial junction. The tumors seemed to arise from the serosa or from the serosa and underlying lymphatic capillaries. The lesions may also have had an origin in endometriosis as the multiparity of all the mice was a common feature.