Cáceres Ramos, Sara Cristina

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Sara Cristina
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Cáceres Ramos
Universidad Complutense de Madrid
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Now showing 1 - 10 of 13
  • Publication
    Blocking Estrogen Synthesis Leads to Different Hormonal Responses in Canine and Human Triple Negative Inflammatory Breast Cancer
    (MDPI, 2021-10-02) Cáceres Ramos, Sara Cristina; Beatriz Monsalve; Angela Alonso-Diez; Belén Crespo; Illera Del Portal, Josefina María; Andrés Gamazo, Paloma Jimena De; Silván Granado, Gema; Illera Del Portal, Juan Carlos
    Blocking estrogen synthesis by inhibitors of estrogen synthesis is a widely used therapy against estrogen receptor-positive tumors. However, these therapies are less effective in negative expression tumors. Therefore, this study determined the effectiveness of anti-aromatase and anti-sulfatase therapies in canine and human inflammatory breast cancer. Cell cultures and xenografts from IPC-366 and SUM149 were treated with different doses of letrozole (anti-aromatase) and STX-64 (anti-sulfatase), in order to observe their effectiveness in terms of cell proliferation, tumor progression, and the appearance of metastases and hormonal profiles. The results revealed that both treatments are effective in vitro since they reduce cell proliferation and decrease the secreted estrogen levels. In xenograft mice, while treatment with letrozole reduces tumor progression by 30-40%, STX-64 increases tumor progression by 20%. The hormonal results obtained determined that STX-64 produced an increase in circulating and intratumoral levels of estradiol, which led to an increase in tumor progression. However, letrozole was able to block estrogen synthesis by decreasing the levels of circulating and intratumoral estrogen and thus slowing down tumor progression. In conclusion, letrozole can be an effective treatment for canine and human inflammatory breast cancer. The knowledge of the hormonal profile of breast tumors reflects useful information on the effectiveness of different endocrine treatments.
  • Publication
    Tumor Growth Progression in Ectopic and Orthotopic Xenografts from Inflammatory Breast Cancer Cell Lines
    (MDPI, 2021-09-13) Cáceres Ramos, Sara Cristina; Alonso-Diez, Angela; Crespo, Belén; Peña Fernández, Laura Luisa; Illera Del Portal, Josefina María; Silván Granado, Gema; Andrés Gamazo, Paloma Jimena De; Illera Del Portal, Juan Carlos
    Xenografts can grow in immunosuppressed hosts, such as SCID mice, and tumor material can be injected into hosts either ectopically or orthotopically. Choosing the correct model to use is a crucial step in animal research. The aim of this study was to report the differences between ectopic and orthotopic xenografts in tumor progression, metastasis capacity, histological features, and steroid hormone profiles in xenografts from the cIMC (canine inflammatory mammary cancer) cell line IPC-366 and hIBC (human inflammatory breast cancer) cell line SUM149. To achieve this purpose, 40 female mice 6–8 weeks old were inoculated with IPC-366 and SUM149 cells subcutaneously (ectopic models) or into mammary fat pad (orthotopic models). Mice were monitored for tumor progression and appearance of metastases, and generated tumors were analyzed in terms of histological examination and steroid hormone production. The results revealed differences in tumor appearance and percentage of metastasis between ectopic and orthotopic models, which were higher in the ectopic xenografts from both cell lines. However, both models had similar characteristics of tumor progression, histological features, and steroid hormone secretion profiles. We show that the ectopic model can be validated as a good and useful model of tumor development in addition to, not contrary to, the orthotopic model in breast cancer research.
  • Publication
    The inhibition of steroid hormones determines the fate of IPC-366 tumor cells, highlighting the crucial role of androgen production in tumor processes
    (Elsevier, 2023-06-01) Crespo, Belen; Cáceres Ramos, Sara Cristina; Silván Granado, Gema; Illera Del Portal, Josefina María; Illera Del Portal, Juan Carlos
    Inflammatory mammary cancer (IMC) is a disease that affects female dogs. It is characterized by poor treatment options and no efficient targets. However, anti-androgenic and anti-estrogenic therapies could be effective because IMC has a great endocrine influence, affecting tumor progression. IPC-366 is a triple negative IMC cell line that has been postulated as a useful model to study this disease. Therefore, the aim of this study was to inhibit steroid hormones production at different points of the steroid pathway in order to determine its effect in cell viability and migration in vitro and tumor growth in vivo. For this purpose, Dutasteride (anti-5αReductase), Anastrozole (anti-aromatase) and ASP9521 (anti-17βHSD) and their combinations have been used. Results revealed that this cell line is positive to estrogen receptor β (ERβ) and androgen receptor (AR) and endocrine therapies reduce cell viability. Our results enforced the hypothesis that estrogens promote cell viability and migration in vitro due to the function of E1SO4 as an estrogen reservoir for E2 production that promotes the IMC cells proliferation. Also, an increase in androgen secretion was associated with a reduction in cell viability. Finally, in vivo assays showed large tumor reduction. Hormone assays determined that high estrogen levels and the reduction of androgen levels promote tumor growth in Balb/SCID IMC mice. In conclusion, estrogen levels reduction may be associated with a good prognosis. Also, activation of AR by increasing androgen production could result in effective therapy for IMC because their anti-proliferative effect.
  • Publication
    Establishment and Characterization of a New Cell Line of Canine Inflammatory Mammary Cancer: IPC-366
    (Public Library of Science, 2015-03-25) Cáceres Ramos, Sara Cristina; Peña Fernández, Laura Luisa; Andrés Gamazo, Paloma Jimena De; Illera Del Portal, Josefina María; Lopez, Mirtha S.; Woodward, Wendy A.; Reuben, James M.; Illera Del Portal, Juan Carlos
    Canine inflammatory mammary cancer (IMC) shares epidemiologic, histopathological and clinical characteristics with the disease in humans and has been proposed as a natural model for human inflammatory breast cancer (IBC). The aim of this study was to characterize a new cell line from IMC (IPC-366) for the comparative study of both IMC and IBC. Tumors cells from a female dog with clinical IMC were collected. The cells were grown under adherent conditions. The growth, cytological, ultrastructural and immunohistochemical (IHC) characteristics of IPC-366 were evaluated. Ten female Balb/SCID mice were inoculated with IPC-366 cells to assess their tumorigenicity and metastatic potential. Chromosome aberration test and Karyotype revealed the presence of structural aberration, numerical and neutral rearrangements, demonstrating a chromosomal instability. Microscopic examination of tumor revealed an epithelial morphology with marked anysocytosis. Cytological and histological examination of smears and ultrathin sections by electron microscopy revealed that IPC-366 is formed by highly malignant large round or polygonal cells characterized by marked atypia and prominent nucleoli and frequent multinucleated cells. Some cells had cytoplasmic empty spaces covered by cytoplasmic membrane resembling capillary endothelial cells, a phenomenon that has been related to s vasculogenic mimicry. IHC characterization of IPC-366 was basal-like: epithelial cells (AE1/AE3+, CK14+, vimentin+, actin-, p63-, ER-, PR-, HER-2, E-cadherin, overexpressed COX-2 and high Ki-67 proliferation index (87.15 %). At 2 weeks after inoculating the IPC-366 cells, a tumor mass was found in 100 % of mice. At 4 weeks metastases in lung and lymph nodes were found. Xenograph tumors maintained the original IHC characteristics of the female dog tumor. In summary, the cell line IPC-366 is a fast growing malignant triple negative cell line model of inflammatory mammary carcinoma that can be used for the comparative study of both IMC and IBC.
  • Publication
    Long‐Term Exposure to Isoflavones Alters the Hormonal Steroid Homeostasis‐Impairing Reproductive Function in Adult Male Wistar Rats
    (MDPI, 2023-03-02) Cáceres Ramos, Sara Cristina; Crespo, Belen; Alonso Diez, Angela; Andrés Gamazo, Paloma Jimena De; Millán Pastor, María Pilar; Silván Granado, Gema; Illera Del Portal, Josefina María; Illera Del Portal, Juan Carlos
    The consumption of isoflavones is gaining popularity worldwide due to their beneficial effects on health. However, isoflavones are considered to be endocrine disruptors and cause deleterious effects on hormone‐sensitive organs, especially in males. Therefore, this study aimed to deter‐ mine if a continuous and prolonged exposure to isoflavones in adult males altered the endocrine axis effect of testicular function. For this purpose, seventy‐five adult male rats were administered with low and high mixtures of isoflavones (genistein and daidzein) for 5 months. The determination of steroid hormones (progesterone, androstenedione, dehydroepiandrosterone, testosterone, dihydrotestosterone, 17β‐estradiol, and estrone sulphate) was carried out in serum and testicular homogenate samples. Sperm quality parameters and testicular histology were also determined. The results revealed that low and high doses of isoflavones promote a hormonal imbalance in androgen and estrogen production, resulting in a decrease in circulating and testicular androgen levels and an increase in estrogen levels. These results are associated with a reduction in the sperm quality parameters and a reduction in the testicular weight, both in the diameter of the seminiferous tubules and the height of the germinal epithelium. Altogether, these results suggest that a continuous ex‐ posure to isoflavones in adult male rats causes a hormonal imbalance in the testes that disrupts the endocrine axis, causing defects in testicular function.
  • Publication
    Non-Invasive Determination of Annual Fecal Cortisol, Androstenedione, and Testosterone Variations in a Herd of  Male Asian Elephants (Elephas maximus) and Their Relation to Some Climatic Variables
    (MDPI, 2021-09-17) Andrés Gamazo, Paloma Jimena De; Cáceres Ramos, Sara Cristina; Belén Crespo; Silván Granado, Gema; Illera Del Portal, Juan Carlos
    The measurement of stress and reproductive hormones in wild animal species by non-invasive methods is of special interest. To assess whether the adrenal and gonadal hormones show annual variations in male Asian elephants (Elephas maximus) and to evaluate whether there is any influence of climatic variables on hormonal secretion, fecal samples were taken from a herd of 7 Asian elephants over a 14-month period to subsequently determine the concentrations of testosterone (T), androstenedione (A4), and cortisol (C) by a validated immunoassay technique. Data referring to three climatic variables in the place and period of study were collected, namely monthly mean values of temperature, humidity and rainfall. Levels of T and A4 showed two major increases in July (T: 1088.35 ± 131.04 ng/g; A4: 480.40 ± 50.86 ng/g) and October (T: 825.09 ± 31.60 ng/g; A4: 319.96 ± 32.69 ng/g) (p < 0.05). Our results show a secretion of fecal androgens dependent on temperature (T and A4), and humidity (T). Male musth was detected during the initial increases of T and A4 levels. The highest concentrations of C were observed in September (156.67 ± 60.89 ng/g) (p < 0.05), probably due to the stressful fights that occurred during the musth period. The observed results of the fecal levels of T, A4 and C were similar to those obtained by invasive methods. In conclusion, fecal secretion of the three hormones in these captive male Asian elephants showed variations related in some cases to different weather factors.
  • Publication
    Physiological Stress Responses in Cattle Used in the Spanish Rodeo
    (MDPI, 2023-08-17) Cáceres Ramos, Sara Cristina; Moreno, Julia; Crespo, Belen; Silván Granado, Gema; Illera Del Portal, Juan Carlos
    Certain events can cause distress in cattle. In Spain, there is a sport similar to rodeo called persecution and takedown, in which calves are harassed and knocked down by riders. In this study, the physiological stress response of calves (n = 260) is assessed by measuring hormonal physiological parameters. Salivary samples were collected from Salers (n = 110) and Lidia (n = 150) calves before, during, and after the persecution and takedown event. The hormones epinephrine, cortisol, serotonin, and dopamine were determined in saliva samples using enzyme-immunoassay techniques. The results obtained revealed that epinephrine and cortisol levels increased during the event in Salers calves, with a significant increase (p < 0.05) in the case of epinephrine, although after the event, these values returned to their initial state. Therefore, this sport supposes an assumable punctual stressor stimulus for the animal. In contrast, in Lidia calves, cortisol and epinephrine levels decreased, with a significant decrease (p < 0.05) in the case of cortisol, which may be related to the temperament of this breed and facing a stressful situation in a different manner. This is confirmed by serotonin and dopamine levels that were altered in Lidia calves with respect to the other group studied. In conclusion, the sport of persecution and takedown produces a physiological response of adaptive stress assumable for the animals
  • Publication
    Anti-Angiogenic Treatments Interact with Steroid Secretion in Inflammatory Breast Cancer Triple Negative Cell Lines
    (MDPI, 2021-07-21) Alonso Diez, Angela; Cáceres Ramos, Sara Cristina; Peña Fernández, Laura Luisa; Crespo, Belen; Illera Del Portal, Juan Carlos
    Human inflammatory breast cancer (IBC) is a highly angiogenic disease for which an-tiangiogenic therapy has demonstrated only a modest response, and the reason for this remains unknown. Thus, the purpose of this study was to determine the influence of different antiangiogenic therapies on in vitro and in vivo steroid hormone and angiogenic growth factor production using canine and human inflammatory breast carcinoma cell lines as well as the possible involvement of sex steroid hormones in angiogenesis. IPC-366 and SUM149 cell lines and xenotransplanted mice were treated with different concentrations of VEGF, SU5416, bevacizumab and celecoxib. Steroid hormone (progesterone, dehydroepiandrostenedione, androstenedione, testosterone, dihydrotestos-terone, estrone sulphate and 17β-oestradiol), angiogenic growth factors (VEGF-A, VEGF-C and VEGF-D) and IL-8 determinations in culture media, tumour homogenate and serum samples were assayed by EIA. In vitro, progesterone-and 17β-oestradiol-induced VEGF production promoting cell proliferation and androgens are involved in the formation of vascular-like structures. In vivo, intratumoural testosterone concentrations were augmented and possibly associated with decreased metastatic rates, whereas elevated E1SO4 concentrations could promote tumour progression after antiangiogenic therapies. In conclusion, sex steroid hormones could regulate the production of angiogenic factors. The intratumoural measurement of sex steroids and growth factors may be useful to develop preventive and individualized therapeutic strategies.
  • Publication
    In vitro and in vivo effect of flutamide on steroid hormone secretion in canine and human inflammatory breast cancer cell lines
    (Wiley, 2017-06-06) Cáceres Ramos, Sara Cristina; Monsalve, B.; Peña Fernández, Laura Luisa; Andrés Gamazo, Paloma Jimena De; Alonso‐Diez, Ángela; Illera Del Portal, Josefina María; Woodward, W. A.; Reuben, J. M.; Silván Granado, Gema; Illera Del Portal, Juan Carlos
    The aim was to study the effects of flutamide on cell proliferation, in vivo tumour growth andsteroid production in canine and human IBC cell lines. IPC-366 and SUM149 cell cultures wereexposed to flutamide concentrations for 72 hours. Additionally, IPC-366 and SUM149 xeno-transplanted mice were treated subcutaneously with flutamide 3 times a week for 2 weeks.Steroid hormones determination in culture media, serum and tumour homogenates (pregneno-lone, progesterone, androstenedione, testosterone, dihydrotestosterone, 17β-oestradiol andoestrone sulphate) were assayed by EIA. in vitro cell proliferation percentages showed adecrease in all flutamide dosages in IPC-366 and SUM149. in vivo flutamide reduced tumoursize by 55% to 65%, and metastasis rates decreased. In treated groups, androgen levels in cul-ture media, serum and tumour homogenates were increased as oestrogen levels decreased.These results suggest that flutamide treatment inhibits cell proliferation and promotes tumourreduction by increasing androgen levels and also support future therapy approaches
  • Publication
    Canine cell line, IPC‐366, as a good model for the study of inflammatory breast cancer
    (Wiley, 2016-05-05) Cáceres Ramos, Sara Cristina; Peña Fernández, Laura Luisa; Lacerda, L.; Illera Del Portal, Josefina María; Andrés Gamazo, Paloma Jimena De; Larson, R. A.; Gao, H.; Debeb, B. G.; Woodward, W. A.; Reuben, J. M.; Illera Del Portal, Juan Carlos
    Inflammatory breast cancer (IBC) is an aggressive type of cancer with poor survival in women. Inflammatory mammary cancer (IMC) in dogs is very similar to human IBC and it has been proposed as a good surrogate model for study the human disease. The aim was to determine if IPC-366 shared characteristics with the IBC cell line SUM149. The comparison was conducted in terms of ability to grow (adherent and nonadherent conditions), stem cell markers expression using flow cytometry, protein production using western blot and tumorigenic capacity. Our results revealed that both are capable of forming long-term mammospheres with a grape-like morphology. Adherent and nonadherent cultures exhibited fast growth in vivo. Stem cell markers expressions showed that IPC-366 and SUM149 in adherent and nonadherent conditions has mesenchymal-like characteristics, E-cadherin and N-cadherin, was higher in adherent than in nonadherent cultures. Therefore, this study determines that both cell lines are similar and IPC-366 is a good model for the human and canine disease.