Inguinal Glands Research Articles

Integrated Study of Canine Mammary Tumors Histopathology, Immunohistochemistry, and Cytogenetic Findings.

Cancer is a complex pathological condition associated with substantial rates of mortality and morbidity in both humans and animals. Mammary gland tumors in intact female dogs are the most prevalent neoplasms. Surgical intervention remains the primary treatment choice. Alternative therapeutic options have emerged, with histopathological examination being fundamental to confirm the diagnosis and to decide the best therapy. This research focused on the clinicopathological, immunohistochemical, and cytogenetic aspects of canine mammary tumors (CMTs). Most of the animals were mixed-breed, with the majority being older than seven years, and only 16.7% had been spayed before surgery. Caudal abdominal and inguinal mammary glands were the most affected, with regional mastectomy being the predominant treatment (75.0%). Of all the tumors, 29.1% were benign, while 70.9% were malignant. Complex adenoma was the most common benign tumor, whereas tubulopapillary carcinoma was the most common malignant type. Grade III tumors (17.6%) were the least encountered, while grades I and II exhibited a similar prevalence (41.2%). All the carcinomas were classified as luminal, and cytogenetics analysis demonstrated a high chromosomal instability with significant aneuploidy observed in all cases and polyploidy detected in 62.5%. This study holds significance as canine and human breast cancers share similar characteristics, suggesting that dogs could be a valuable model for human breast cancer research. Further studies with larger sample sizes are needed to enhance our understanding of CMTs.

Mixed Canine Mammary Gland Tumour in a 10 Year Old Lhasa Apso Bitch Histopathological Evaluation and Surgical Management

Mixed mammary gland tumors are the most frequent canine mammary gland neoplasms with a high incidence rate among females, however, there is paucity of studies that describe their clinic-pathological presentations and management approaches. This case evaluated the clinic-pathological data and management of mixed mammary gland tumors. A 10-year-old Lhasa Apso bitch weighing 11.4kg was referred to the University of Jos Veterinary Teaching Hospital with a ventral abdominal mass. Clinical examination revealed an enlarged left inguinal mammary gland with two palpable masses. The inguinal region was aseptically prepared for surgery and anesthesia achieved by the administration of 1% atropine sulphate (Atropine® - Shanxi Shuguang Pharmaceutical Co., Ltd., Qixian, China) and Chlorpromazine as preanesthetics and 50mg/mL Ketamine hydrochloride (Jawa ketamine® - Swiss Parenterals Ltd, Gujarat, India) + 2% Xylazine (Alfasan, Woerden-Holland) as induction and maintenance anesthetics. The glandular, connective/fibrous and fatty tissues of the mammary gland were carefully dissected to achieve the complete excision of the encapsulated mammary tumour masses before the reconstruction of the resulting defect. Postoperatively, penicillin and streptomycin, piroxicam, vitamin B complex, dexamethasone, vincristine sulphate and ivermectin were administered. The excised masses histologically presented numerous tubules with some containing mucin. Also there were the presence of acini with neoplastic epithelial cells and myoepithelial cells, cartilage and bony trabeculae. Surgical debulking with adjunctive immuno-chemotherapy was curative for the mixed mammary gland tumours in this bitch.

Spontaneous fibroadenoma in a twenty-one-week-old female Wistar rat – a case report

We describe the characteristic macro- and microscopic findings of a new case of spontaneous fibroadenoma in a 21-week-old, non-treated female Wistar rat. A mobile and non-ulcerated mass was detected affecting the caudal inguinal mammary gland. At necropsy, the mass was 5.5 cm in size, spherical in shape, and well demarcated with a smooth surface. The cut surface was pink, with a multilobulated pattern. Microscopically, fibroadenoma was composed of dense connective tissue surrounding luminal epithelial tissue, organized in tubular structures. The luminal epithelial cells were typical and, in some areas, presented lipid vacuoles in the cytoplasm and proteinaceous material in the lumen of the tubules. The interlobular and intralobular stroma showed variable amounts of mast cells. Immunohistochemically, epithelial cells expressed both oestrogen and progesterone receptors in the nucleus. Fibroadenoma is a frequent tumour, but it is uncommon at an early age.

Clinicopathological Diversity and Epidemiological Aspects of Canine and Feline Mammary Gland Tumors in Tehran: A Survey (2020-2022)

Background: Mammary tumors are common in dogs and cats. They are models for investigating carcinogenesis and designing treatment protocols that benefit human beings. Senescence, sex, and reproductive status affect the development of such neoplasms. Objectives: In Iran’s absence of a national animal tumor registry, the present study determined clinicopathological and epidemiological aspects of canine and feline mammary tumors in referral cases of four veterinary practices across Tehran from 2020 to 2022. Here, the incidence and types of canine and feline mammary tumors are described, in addition to sex, reproductive status, age, breed, the affected mammary gland(s), grades, lymphatic invasion, and lymph node metastases. Methods: All canine and feline patients with masses in the mammary gland region were considered in this study. The resected tumors and occasional lymph nodes were macroscopically scrutinized. Hematoxylin-Eosin slides were reviewed by light microscopy and immunohistochemistry was utilized when necessary. Results: Of the 76 dogs and eight cats, 100% were females, and the majority were intact. Most patients were 10-11 years old. Purebreds were the most frequent referrals. In some patients, more than one mammary gland had developed neoplasm, i.e. 141 affected glands in 76 bitches and nine affected glands in eight queens. Tumors were presented in both chains and even on the ventral midline, with an increased preponderance of caudally located glands. Thus, the caudal-most glands, i.e. inguinal and caudal abdominal glands, constituted 31.2% and 66.7% of the affected glands in bitches and queens, respectively. Intraductal papillary carcinoma (17%) and complex carcinoma (16.3%) had the highest incidence in dogs. The most commonly observed lesions in cats were lobular hyperplasia with atypia, and duct ectasia, each encompassing 22.3% of the affected glands. Most canine neoplasms were grade I (90.3%), while grade II neoplasms had the highest incidence in cats (50%). Lymphatic invasion and lymph node metastases were seen in canine anaplastic carcinoma, solid carcinoma, and complex carcinoma, as well as feline comedocarcinoma and tubular carcinoma. Conclusion: The risk of developing malignant tumors increases as the individual ages, and generally, caudally located mammary glands in intact purebred females are at increased risk. Moreover, anaplastic carcinomas must be precisely examined, both clinically and histopathologically, for lymph node metastases.

Superficial anatomic landmarks can be used to triangulate the location of canine peripheral lymphocentrums: superficial cervical, axillary, and superficial inguinal.

To utilize the geometry of superficial anatomic landmarks to guide incisional location and orientation for peripheral lymphadenectomy, document deep anatomic landmarks for lymphocentrum identification, and develop novel surgical approaches to the superficial cervical, axillary, and superficial inguinal lymphocentrums in dogs. 12 canine cadavers. 2 cadavers were used for a pilot investigation to determine optimal body positioning, select superficial anatomic landmarks for lymphocentrum identification, and evaluate novel surgical approaches to the 3 lymphocentrums. These lymphocentrums were then dissected in 10 additional cadavers using these novel surgical approaches. Measurements of the distances from lymphocentrum to landmark and between landmarks were obtained for each lymphocentrum. Deep anatomic landmarks were recorded for each dissection. The mean and SD were calculated for each measurement and used to develop geometric guidelines for estimating the location of each lymphocentrum for these surgical approaches. Each peripheral lymphocentrum was found in the same location relative to the respective, predetermined, superficial, anatomic boundaries in all cadavers. Briefly, the superficial landmarks to each lymphocentrum were as follows: (1) superficial cervical: wing of atlas, acromion process of scapula, greater tubercle of humerus; (2) axillary: caudal border of transverse head of superficial pectoral muscle, caudal triceps muscle, ventral midline; and (3) superficial inguinal: origin of pectineus muscle, ipsilateral inguinal mammary gland, ventral midline. The proposed superficial and deep surgical landmarks were identified within every cadaver. The previously undescribed surgical approaches were effective for lymphocentrum identification. Anatomic landmarks provided in this study may help reduce surgical time and tissue trauma during peripheral lymphadenectomy in dogs. This study was also the first to describe a surgical approach to the superficial inguinal lymphocentrum and ventral approaches to the superficial cervical and axillary lymphocentrums and provided previously unpublished anatomic landmarks for a lateral approach to the superficial cervical lymphocentrum.

Comparative analysis of male reproductive accessory glands in bats Histiotus velatus (Vespertilionidae), Molossus rufus (Molossidae), and Peropteryx leucoptera (Emballonuridae).

Despite the high number of species and wide geographic dispersion, reproductive accessory glands (RAGs) of bats have traditionally received little attention in the literature, with some species not even having a basic description of their composition and structure. Thus, this study aimed to analyze and compare the composition, anatomy, and histology of male RAGs of bat species belonging to three of the largest (cosmopolitan) bat families: Vespertilionidae (Histiotus velatus), Molossidae (Molossus rufus), and Emballonuridae (Peropteryx leucoptera), in order to understand the variations in the bat RAGs. The results showed that the RAGs of H. velatus, M. rufus, and P. leucoptera are composed of an intra-abdominal prostatic complex, associated with the urethra, urethral glands, and a pair of inguinal bulbourethral glands; without ampullary glands or seminal vesicles. The prostatic complex can be composed of two (M. rufus and P. leucoptera) or three (H. velatus) prostatic regions, and can be compact (P. leucoptera), semi-lobed (M. rufus), or multilobed (H. velatus). Each prostatic region has unique and distinct characteristics, with the ventral region presenting a holocrine nature, exclusive to bats; while the dorsal and/or dorsolateral regions have similar characteristics to the ventral prostate of rats and to the human peripheral zone.

Mother’s scent for motherless neonates: Responses of artificially reared lambs to ewe’s inguinal wax odor

Mammalian newborns depend on their mother’s milk to satisfy their initial needs of protection and nutrition. They reach the source of milk in following visual, tactile and olfactory cues. In particular, parturient ewes produce an odorous wax in the inguinal glands close to the teats. When presented separately to newly born lambs, this inguinal wax (IW) elicits arousal, head orientation, licking and increased respiratory rate indicative of their avidity for it. The present study assessed whether transferring IW into the environment of artificially fed lambs would improve their responses to the novelty of the situation. We first assessed whether suckled lambs preferred an IW-scented teat to a scentless control teat. Then, we assessed whether a teat odorized with IW was more easily learned as suckable relative to a control teat. Finally, the lambs’ growth performance from postnatal days (PND) 0 and 20 was compared in groups reared with or without IW spread on the milk-feeder in their home pen. The behavioral assays did not evidence any significant effect of IW odor on previously suckled lambs’ attraction and appetence responses. However, relative to the scentless control condition, being exposed to an IW-smeared milk-feeder led to a higher body weight at 20 days after birth. In the conditions of the present study, namely after suckling initiation, IW odor appeared not to be a strong determinant of short-term attraction or appetitive behavior in neonate lambs. The continued presence of IW, a familiar odor, in the artificial suckling context may improve artificially-reared lambs’ emotional state that may affect their weight gain.

Comparison of intratumor and local immune response between MV X-ray FLASH and conventional radiotherapies

Background/PurposeInvestigating the antitumor effect and intratumor as well as local immune response in breast cancer-bearing mice after MV X-ray ultra-high dose rate radiotherapy (FLASH-RT) and conventional dose rate radiotherapy (CONV-RT). Materials/MethodsSix-week-old female C57BL/6 mice were inoculated subcutaneously with Py8119 and Py230 breast tumor cells in the inguinal mammary gland and administered 10 Gy abdominal 6 MV X-ray FLASH-RT (125 Gy/s) or CONV-RT (0.2 Gy/s) 15 days after tumor inoculation. Tumor and spleen tissues were obtained at different time points post-irradiation (PI) for analysis of immune cell infiltration using flow cytometry and immunohistochemical (IHC) staining. Intestine tissues were collected 3 days PI to evaluate normal tissue damage and immune cell infiltration. ResultsBoth FLASH-RT and CONV-RT significantly delayed tumor growth. Flow cytometry showed increased CD8+/CD3 + and CD8+/CD4 + ratios, and IHC confirmed a similar increased CD8 + T cell infiltration at 2 weeks PI in Py8119 tumor tissues in both irradiation groups. No statistical difference was observed between the irradiation groups in terms of tumor growth and increased T cell infiltration in the tumor. Unexpectedly, significantly smaller spleen weight and substantially higher CD8+/CD3 + and lower CD4+/CD3 + ratios were observed in the spleens of the FLASH-RT group than in the spleens of the non-irradiated control and CONV-RT groups 4 weeks PI. Pathological analysis revealed severe red pulp expansion in several spleens from the CONV-RT group, but not in the spleens of the FLASH-RT group. Reduced intestinal damage, macrophage and neutrophil infiltration were observed in the FLASH-RT group compared with CONV-RT group. ConclusionsFLASH-RT and CONV-RT effectively suppressed tumor growth and promoted CD8 + T cell influx into tumors. FLASH-RT can induce different splenic immune responses and reduce radiation-induced damage in the spleen and intestine, which may potentially enhance the therapeutic ratio of FLASH-RT.

The Immune Response and Intestinal Injury after X-Ray FLASH Irradiation in Murine Breast Cancer Transplanted Models

<h3>Purpose/Objective(s)</h3> The present study investigated the anti-tumor effect, immune response, and intestinal injury in breast cancer-bearing mice after ultra-high dose rate radiotherapy (FLASH-RT) and conventional dose rate radiotherapy (CONV-RT). <h3>Materials/Methods</h3> Six-week-old female C57BL/6 mice were inoculated subcutaneously with Py8119 and Py230 breast tumor cells in the inguinal mammary gland, and received 10 Gy abdominal 6 MeV X-ray FLASH-RT (>100 Gy/s) or CONV-RT (0.2 Gy/s) 15 days after tumor inoculation. EBT3 radiographic films were used to confirm the dose. Tumor samples were obtained 2 weeks post-irradiation (PI) in Py8119 tumor-bearing mice, spleen tissues were collected 4 weeks PI in Py230 tumor-bearing mice. Flow cytometry (FC) was performed with tumor and spleen tissues and immunohistochemistry (IHC) staining was performed in tumor tissues to test CD3+, CD4+, and CD8+ T lymphocytes. The number and length of remaining crypts were measured to evaluate acute intestine damage 3 days PI. <h3>Results</h3> Both FLASH-RT and CONV-RT significantly reduced the tumor weights. FC showed increased CD8+/CD3+ and CD8+/CD4+ ratios in tumor tissues and IHC confirmed a similar CD8+ T cells percentage 2 weeks PI, but there is no significant difference between FLASH and CONV groups. Surprisingly, significantly smaller spleen weight and substantially higher CD8+/CD3+ and CD8+/CD4+ ratios in the spleen in FLASH compared with non-irradiated control and CONV groups 4 weeks PI, indicating FLASH might stimulate a systematic immune response. FLASH irradiated mice had more remaining crypts and significantly longer crypt length than CONV irradiated mice, indicating a normal tissue sparing effect of FLASH-RT. <h3>Conclusion</h3> FLASH-RT and CONV-RT effectively suppressed tumor growth and promoted CD8+ T cell influx into the tumor. FLASH-RT resulted in a smaller weight and a higher proliferative rate of CD8+ T cells in the spleen than CONV-RT, which might indicate a different systematic immune effect between FLASH-RT and CONV-RT. FLASH-RT significantly spared the intestine from early damage.

Metastatic mammary tubulopapillary carcinoma in a captive black jaguar (Panthera onca)

AbstractA 12‐year‐old female captive jaguar (Panthera onca) developed sudden severe respiratory distress and died close to the onset of clinical signs. The animal underwent mastectomy to remove neoplasms in the mammary glands 2 years prior to death. During the post‐mortem examination, multiple nodules were found in the remaining left inguinal mammary glands. Similar lesions were found in other organs. Microscopically, neoplasms were characterised by a tubulopapillary pattern with papillary projections into the central lumen of newly formed tubules (tubulopapillary mammary carcinoma). Immunohistochemistry (IHC) for oestrogen receptor, progesterone receptor and high molecular weight cytokeratin on the mammary tissue site and a metastatic site was performed with positive results. IHC for Ki‐67 was performed in the mammary lesion with positive labelling in 50% of the cells. In captive felids, malignant neoplasms may be aggressive with limited therapeutic options. Thus, attention is needed in anticipating arising tumours to support the use of control therapies and the long‐term preservation of captive jaguars.

Abstract 1350: The role of phosphatidylserine scramblases in tumor progression

Abstract Introduction: Phosphatidylserine (PS), an anionic phospholipid, is asymmetrically distributed in the inner leaflet of the phospholipid bilayer in normal cells under homeostasis. However, PS is constitutively externalized in the tumor microenvironment (TME); on viable cells that undergo stress, such as hypoxic tumor cells, stressed tumor vascular endothelial cells, as well as on cells undergoing apoptosis. This high PS harbors a pro-tumorigenic micro-environment, as myeloid cells expressing PS receptors (Mertk, Tyro3 and Axl) engage with externalized PS and secrete immunosuppressive cytokines. PS is externalized on viable cells by a calcium activated scramblase TMEM16F and on apoptotic cells by a caspase activated scramblase called Xkr8. Here, to study the mechanisms by which PS is externalized in the TME, we hypothesize that TMEM16F and Xkr8 are the major scramblases responsible for creating an immune suppressive milieu in the tumor microenvironment. Methods: To study the mechanisms of PS dysregulation in the tumor microenvironment, TMEM16F and Xkr8 were knocked out in E0771 murine breast cancer cell line using CRISPR/Cas9. The knockouts were validated by western blotting, q-RT-PCR and surveyor assays. Results: TMEM16F KO E0771 cells express lower basal levels of PS compared to WT E0771 cells when detected by Annexin V staining by flow cytometry. TMEM16F KO cells are also less responsive to activation by calcium ionophore. TMEM16F KO, Xkr8 KO and WT E0771 cells have similar viability and migration patterns in response to Gas6, indicating that the cells themselves do not have altered oncogenic potential. TMEM16F KO E0771 cells injected into the inguinal mammary gland fat pad of C57BL6 syngeneic mice showed modest but significantly reduced tumor growth compared to the E0771 WT tumors, suggesting that TMEM16F mediated PS externalization could play a role in exacerbating tumor progression. Conclusion: TMEM16F driven PS externalization contributes to tumor growth. The effect of TMEM16F KO on immune regulation of the tumor milieu will be discussed. These data corroborate previous studies targeting PS in tumors therapeutically using anti-PS antibodies and suggests a role for scramblases in pleiotropic immune-suppression in the tumor. Citation Format: Varsha Gadiyar, Viralkumar Davra, David Calianese, Kevin Lahey, Raymond B. Birge. The role of phosphatidylserine scramblases in tumor progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1350.

Extragenital Pathology and Immunocompetent Cells Relations of Lactating Breast Gland and Offspring Jejunum

Researched the effect of chronic toxic maternal hepatitis on the cytometric features of immunocompetent cells (ICCls) of mammary gland tissues of the female and the jejunum of the offspring during breastfeeding. For morphological researches, pieces of the right inguinal mammary gland of female outbred rats with heliotrine hepatitis and the jejunum of the lean intestine of the offspring on days 1, 3, 7, 15 and 21 of lactation were used. Cytometric researches were carried out on semi-thin sections stained with methylene blue and pyronin G. It was established that in the last stages of pregnancy and in the first week after the onset of lactation, there is an increase in migration to the terminal secretory sections of the mammary gland of the ICCls, which indicates the participation of the mammary glands in the transfer of adoptive immunity to offspring and in maintaining the immune homeostasis of the small intestine, which decreases as the immune apparatus of the small intestine develops. A decrease in the number of ICCls migrating to the lactating mammary gland in case of mother's CTH negatively affects both immune adaptation and the structural and functional development and maturation of the immune apparatus of the jejunum of the offspring during breastfeeding.

Time-restricted feeding alters the efficiency of mammary tumor growth

ABSTRACT Disruption of circadian rhythms has detrimental host consequences. Indeed, both clinical and foundational science demonstrate a clear relationship between disruption of circadian rhythms and cancer initiation and progression. Because timing of food intake can act as a zeitgeber (i.e., entrainment signal) for the circadian clock, and most individuals in the developed world have access to food at all times of the day in a “24/7” society, we sought to determine the effects of timing of food intake on mammary tumor growth. We hypothesized that restricting access to food to during the inactive phase would accelerate tumor growth. Adult female Balb/C mice received a unilateral orthotopic injection of murine mammary carcinoma 4T1 cells into the ninth inguinal mammary gland. Beginning on the day of tumor injection and continuing until the end of the experiment, mice were food restricted to their active phase (ZT12 (lights off)- ZT0 (lights on), inactive phase (ZT0 – ZT12), or had ad libitum access to food. Mice that were food restricted to their inactive phase displayed a significant increase in body mass on days 7 and 14 of tumor growth relative to active phase or ad libitum fed mice. Additionally, mice fed during their inactive phase demonstrated a 20% reduction in food consumption relative to mice fed during their active phase and a 17% reduction in food consumption relative to ab libitum fed mice. Tumor volume was not significantly different between groups. However, food restricting mice to their inactive phase increased mammary tumor growth efficiency (i.e., mg of tumor mass per gram of food intake) relative to mice fed during the active phase and approached significance (p = .06) relative to ad libitum fed mice. To determine a potential explanation for the increased tumor growth efficiency, we examined rhythms of activity and body temperature. Mice fed during the inactive phase displayed significantly disrupted daily activity and body temperature rhythms relative to both other feeding regimens. Together, these data demonstrate that improperly timed food intake can have detrimental consequences on mammary tumor growth likely via disrupted circadian rhythms.

Artificial Light at Night Reduces Anxiety-like Behavior in Female Mice with Exacerbated Mammary Tumor Growth.

Simple SummaryArtificial light at night, initially assumed to be innocuous, is associated with an increased risk for developing mood disorders, sleep disturbances, and cancer. However, the influence of ALAN on affective behavior in tumor-bearing mice has not been investigated. Here, we demonstrate that ALAN reduces the latency to tumor onset and increases terminal tumor volume. Additionally, tumor-bearing mice housed in dark nights exhibit increased anxiety-like behavior which is prevented via housing in ALAN.Artificial light at night (ALAN) is a pervasive phenomenon. Although initially assumed to be innocuous, recent research has demonstrated its deleterious effects on physiology and behavior. Exposure to ALAN is associated with disruptions to sleep/wake cycles, development of mood disorders, metabolic disorders, and cancer. However, the influence of ALAN on affective behavior in tumor-bearing mice has not been investigated. We hypothesize that exposure to ALAN accelerates mammary tumor growth and predict that ALAN exacerbates negative affective behaviors in tumor-bearing mice. Adult (>8 weeks) female C3H mice received a unilateral orthotropic injection of FM3A mouse mammary carcinoma cells (1.0 × 105 in 100 μL) into the fourth inguinal mammary gland. Nineteen days after tumor inoculation, mice were tested for sucrose preference (anhedonia-like behavior). The following day, mice were subjected to an open field test (anxiety-like behavior), followed by forced swim testing (depressive-like behavior). Regardless of tumor status, mice housed in ALAN increased body mass through the first ten days. Tumor-bearing ALAN-housed mice demonstrated reduced latency to tumor onset (day 5) and increased terminal tumor volume (day 21). Exposure to ALAN reduced sucrose preference independent of tumor status. Additionally, tumor-bearing mice housed in dark nights demonstrated significantly increased anxiety-like behavior that was normalized via housing in ALAN. Together, these data reaffirm the negative effects of ALAN on tumorigenesis and demonstrate the potential anxiolytic effect of ALAN in the presence of mammary tumors.

To the question of the classification of the inguinal lymph glands and the sources of their blood supply

The inguinal lymphatic gland, the largest in the human body, was one of the first to which the attention of anatomists was drawn in ancient times.

Investigating the effect of positional variation on mid-lactation mammary gland transcriptomics in mice fed either a low-fat or high-fat diet.

Little attention has been given to the effect of positional variation of gene expression in the mammary gland. However, more research is shedding light regarding the physiological differences that mammary gland location can have on the murine mammary gland. Here we examined the differentially expressed genes between mammary gland positions under either a low-fat diet (LFD) or a high-fat diet (HFD) in the mid-lactation mammary gland (lactation day 11; L11). Three-week old WT C57BL/6 mice were randomly assigned to either a low-fat diet (LFD) or high fat diet (HFD) (n = 3/group) and either the right thoracic mammary gland (TMG) or inguinal mammary gland (IMG) was collected from each dam for a total of 12 unique glands. Within each diet, differentially expressed genes (DEGs) were first filtered by adjusted p-value (cutoff ≤ 0.05) and fold-change (FC, cutoff ≥2). Genes were further filtered by mean normalized read count with a cutoff≥10. We observed that mammary gland position had a significant impact on mammary gland gene expression with either LFD or HFD diet, with 1264 DEGs in LFD dams and 777 DEGs in HFD dams. We found that genes related to snRNP binding and translation initiation were most significantly altered between the TMG and IMG. Although we were not able to discern a molecular mechanism, many small nuclear RNAs and small nucleolar RNAs were differentially expressed between the TMG and IMG responsible for cellular functions such as splicing and ribosome biogenesis, which provides and interesting avenue for future research. Our study supports the hypothesis that collection of the mammary gland from a particular location influences mammary gland gene expression, thereby highlighting the importance for researchers to be vigilant in documenting and reporting which mammary gland they are using for their studies.

Borderline Ovarian Tumor

Ovarian borderline tumors are a group of pathologic tumors that exhibit a higher proliferative activity when compared to benign tumors. Due to the absence of a screening method, ovarian cancer is often diagnosed when the patient already has a complaint, or at an advanced stage. A 24-year-old patient was diagnosed with cystic ovarian neoplasm, the results of physical examination and support support the possibility of malignancy. In this patient, a left salphingo-oophorectomy was chosen instead of cystectomy, this was done considering the size of the tumor mass was large enough so that the normal tissue of the ovary was estimated to be almost absent. From the results of the PA laboratory is cystadenoma multiloculare ovarii mucinosum borderline with this microinvation. The patient found massive ascites which could be classified as high risk. In high-risk stage I borderline ovarian tumors, laparotomy should include hysterectomy and bilateral salpingo-oophorectomy. However, because the patient still expects reproductive function, conservative surgery can be performed by only performing unilateral salpingo-oophorectomy, omentum (left ovary and left tube), left inguinal gland and peritoneal rinses. Additional platinum-based chemotherapy such as carboplatine for 3-6 cycles may be indicated in high-risk patients such as this case. (left ovary and left tube) omentum, left inguinal gland and peritoneal rinses. Additional platinum-based chemotherapy such as carboplatine for 3-6 cycles may be indicated in high-risk patients such as this case. (left ovary and left tube) omentum, left inguinal gland and peritoneal rinses. Additional platinum-based chemotherapy such as carboplatine for 3-6 cycles may be indicated in high-risk patients such as this case.Keywords: Borderline ovarian tumor, conservative surgery

Abstract 107: Identifying the role of fibrocytes in obesity-induced mammary gland fibrosis

Abstract Obesity significantly increases breast cancer risk. In addition, obese breast cancer patients have an overall worsened prognosis. The complex relationship between obesity and breast tumor growth and aggressiveness is still being examined. Within breast adipose tissue, obesity causes a state of chronic, macrophage-driven inflammation. Chronic inflammation is associated with increased extracellular matrix (ECM) deposition, however, the underlying mechanisms are not completely understood. In mouse models, increased collagen within the mammary microenvironment is a risk factor for tumor formation, as well as more aggressive tumors. To understand how obesity affects collagen deposition in the mammary gland, we used a diet-induced obesity mouse model. We demonstrated that there was significantly greater collagen deposition around the mammary ducts of high-fat diet (HFD) fed mice compared to control diet (CD) fed mice. To understand how myeloid lineage cells contribute to this fibrosis, CD11b+ cells were sorted from mammary glands of CD- and HFD-fed mice using magnetic beads. When cultured, a population of these sorted CD11b+ cells formed adherent colonies, and colony formation was significantly increased in the CD11b+ cells isolated from HFD-fed mice. When examined further, these colonies expressed myofibroblast markers smooth muscle actin (SMA) and collagen I. These colony-forming CD11b+ cells are consistent with fibrocytes, which have been studied in both chronic inflammatory and fibrotic diseases, but have not been studied in obesity. Fibrocytes are a multipotent, bone-marrow-derived population of cells that originate as myeloid progenitor cells and have characteristics of both macrophages and myofibroblasts. Consistent with an increase in fibrocytes in the mammary gland, myeloid progenitor cells (CD45+CD11b+CD34+) were significantly increased in the bone marrow of HFD-fed mice, indicating an upregulation in the progenitor cell population for both monocytes/macrophages and fibrocytes. To examine differentiation of fibrocytes within the mammary gland, FACS-isolated myeloid progenitor cells from the bone marrow of GFP positive mice were transplanted into the inguinal mammary glands of HFD-fed CCR2 null mice, which have limited movement of myeloid lineage cells out of the bone marrow. Within the mammary glands of these transplanted mice, we observed GFP positive cells that also expressed SMA. Together, our results suggest that chronic inflammation within the obese mammary gland leads to increased fibrocyte numbers, as well as increased collagen deposition around mammary ducts. The effects of obesity on breast tissue fibrosis, as well as the cells responsible for this fibrosis, must be elucidated to better address the risk of breast tumor development in obese women. Citation Format: Genevra M. Kuziel, Lisa M. Arendt. Identifying the role of fibrocytes in obesity-induced mammary gland fibrosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 107.

A New Species of Scinax Wagler (Amphibia, Anura, Hylidae) from the Atlantic Forest, Southeastern Brazil

The Scinax catharinae clade comprises the S. perpusillus and S. catharinae groups. The S. catharinae group has 38 species, mostly from Brazil's Atlantic Forest. We describe a new species of S. catharinae group based on external morphology, color pattern, and bioacoustics. The new species calls from herbaceous vegetation of slow-flowing streams from Santa Teresa, State of Espírito Santo, southeastern Brazil. The new species is distinguished from species of the S. catharinae group by the following combination of characters: male SVL 24.8–28.3 mm and female SVL 31.2–38.6 mm; males with hypertrophied forearms and inguinal glands; interocular region with a dark blotch not exceeding beyond the anterior margin of tympanic level; black blotches on a whitish-green background on the inguinal region and hidden surfaces of legs; call type A of 0.301–0.883 s, and 12–30 notes emitted at a rate of 31.4–42.0 notes/s. We also provide remarks on its natural history and conservation status.

Two new species of terrestrial-breeding frogs (Anura: Brachycephaloidea) from Cordillera de Colán, Peru

ABSTRACT We describe two new species of terrestrial-breeding frogs from the Cordillera de Colán, in northeastern Peru. We used Parsimony and Maximum Likelihood approaches to infer a molecular phylogeny on a dataset composed of 75 terminals, including three terminals representing the new species, and 4202 bp of concatenated mtDNA and nuDNA fragments. Our phylogenetic analyses support the placement of the two new species in Lynchius and Oreobates, respectively. The new species of Lynchius occurs in two localities from 1,977 to 2,006 m a.s.l., and is characterized by having a dorsum covered by conical tubercles and a brown dorsal coloration lacking a pattern of blotches on the hidden surfaces of flanks and hindlimbs. The new species of Oreobates is only known from one location at 2608 m a.s.l. and is characterized by the absence of axillary and inguinal glands, and the presence of white or cream blotches on the dark brown hidden surfaces of the body.