bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemically-Modified Tetraiodothyroacetic Acid (Tetrac) Induces Cancer Cell Apoptosis and Facilitates Clearance of Apoptotic Debris (Efferocytosis)
Authors: Godugu Kavitha , Lin Hung-yun , Mousa Shaker A , Davis Paul J 
Published: May 2021

Abstract
Tetraiodothyroaetic acid (tetrac) is a derivative of L-thyroxine with anticancer properties. By multiple molecular mechanisms, tetrac and chemically-modified tetrac induce apoptosis in a variety of human cancer cells in vitro and in xenografts. The anticancer activities of tetrac are initiated at the thyroid hormone analogue receptor on the extracellular domain of plasma membrane integrin αvβ3 (PJ Davis et al., Physiol Rev 101:319-352, 2021). Induction of apoptosis in glioblastoma xenograft with chemically modified tetrac (P-bi-TAT) has yielded 90% in volume of grafts that continues after discontinuation of tetrac. In the present study, we show that human glioblastoma xenograft shrinkage in response to P-bi-TAT is associated with local appearance of phagocytic monocytes and clearance of apoptotic debris (efferocytosis). Primary culture xenograft of glioblastoma cells (GBM 052814, kindly provided by the University of Pittsburgh Medical Center, Department of Neurosurgery) and U87-luc (ATCC, Manassas, VA) xenografts were generated in 5-member groups of nude mice for each tumor cell type and for controls. Five days post-implantation, injection of animals was begun with PBS (control) or P-bi-TAT (10 mg/kg body weight). Injection was continued X21 days and animals were then maintained off-treatment for an additional 21 days. Tumors were harvested, formalin-fixed and slide-mounted, then analyzed by TUNEL assay for apoptosis and by anti-CD68 staining for monocytic macrophage content. Histologic analysis (H&E staining) was also carried out. TUNEL analysis and histopathology of both xenograft models revealed more than 90% apoptotic change with 21-days of P-bi-TAT treatment (P &lt;0.001) and persistence of 40% apoptotic change 3 weeks post-discontinuation of drug (P&lt;0.001 vs. end of treatment change). By H&E histology and CD68 analysis, monocytes accounted for more than 90% of the viable cells after 3 weeks’ drug treatment. Sixty percent of the end-of-treatment monocyte population persisted 3 weeks after discontinuation of P-bi-TAT (P &lt;0.001). Histology revealed negligible cell debris after 3 weeks of drug treatment and at 3 weeks post-discontinuation of P-bi-TAT. Thus, the anticancer/pro-apoptotic action of tetrac-containing P-bi-TAT is associated with efferocytosis that contributes to the frank tumor shrinkage that results from P-bi-TAT treatment of human glioblastoma xenografts. This is the first documentation of efferocytosis regulated from the thyroid hormone analogue receptor on tumor cell integrin αvβ3.
Cholecalciferol Mediates Apoptosis in Siha Cervical Cancer Line via Autocrine Mechanisms
Authors: Bhoora Sachin , Pillay Tahir S , Punchoo Rivak 
Published: May 2021

Abstract
Cervical cancer disproportionately affects low-resource countries and is a significant health burden in South Africa. Pre-clinical studies have demonstrated numerous anti-cancer actions of vitamin D metabolites. Here, the anti-cancer action of the vitamin D precursor, cholecalciferol, was investigated in a high-grade cervical cancer cell line, SiHa. SiHa cell cultures were treated with a range of cholecalciferol doses (26 nM, 104 nM, 260 nM and 2600 nM) for 72 hours. Cell count and viability were assessed by crystal violet and trypan blue assays, respectively. Apoptotic cell death was investigated by flow cytometry, which measured mitochondrial membrane potential (∆Ψm), phosphatidylserine (PS) externalisation, effector caspase activation and the expression of DNA damage markers. Additionally, brightfield microscopy and transmission electron microscopy (TEM) were respectively used to characterise morphological and ultrastructural features of apoptosis. Expression of the vitamin D metabolising system (VDMS) – consisting of cholecalciferol activating (CYP2R1 and CYP27A1), calcidiol activating (CYP27B1) and calcidiol inactivating (CYP24A1) enzymes, and the vitamin D receptor (VDR) – was assessed by qPCR and Western blots. Data were analysed using a one-way ANOVA and Bonferroni post-hoc tests and p &lt; 0.05 was considered statistically significant. Significant decreases in cell count (p = 0.011) and cell viability (p &lt; 0.0001) were identified in SiHa cells treated with 2600 nM cholecalciferol. Furthermore, biochemical markers at 2600 nM treatment were significant for apoptosis, and included decreased ∆Ψm (p = 0.0145); increased PS externalisation (p = 0.0439); terminal caspase activation (p = 0.0025); and nuclear damage (p = 0.004). Moreover, biochemical apoptosis was corroborated by classical apoptotic features observed by brightfield microscopy and TEM. Additionally, a significant increase in CYP2R1 gene (p &lt; 0.0001) and protein (p = 0.021) expression, and a converse significant decrease in CYP27B1 gene (p = 0.003) and protein expression (p = 0.031) were observed at 2600 nM cholecalciferol treatment. Furthermore, significant increases in VDR gene (p = 0.033) and protein (p = 0.04) expression, and CYP24A1 gene (p &lt; 0.0001) and protein (p = 0.0274) expression were observed at 2600 nM cholecalciferol. In summary, high-dose cholecalciferol treatment of SiHa cervical cancer cells inhibits cell growth, induces apoptosis, and furthermore, upregulates CYP2R1 and VDR expression. Taken together, these findings suggest that autocrine activation of cholecalciferol to calcidiol may mediate VDR signalling of cell growth inhibition, and apoptosis in SiHa experimental cultures.
Comprehensive Analysis of Clinical Features in Index Cases With Multiple Endocrine Neoplasia Type 1 Refine the Risk Rate for Detection of Mutation Distinguishing Negative-Mutation (Phenocopies) and Positive-Mutation Cases
Authors: Urtremari Betsaida , Carvalho Rafael A , Santana Lucas S , Antonio Louise V , Ribeiro Flavio G , Lugeiro Palloma C , Quedas Elisangela P S , Lourenco Jr Delmar M 
Published: May 2021

Abstract
Background: Index cases clinically diagnosed with multiple endocrine neoplasia type 1 (MEN1) are declared as MEN1 phenocopies if no germline MEN1 mutation is identified. In comparison with positive-mutation cases, most phenocopies have been diagnosed in older age, mainly by association of primary hyperparathyroidism (HPT) and pituitary adenoma (PIT), with HPT predominantly diagnosed as uniglandular disease. Besides that, phenocopies rarely develop a third MEN1-related tumor and are associated with lower morbidity and longer survival. However, all these data are mainly derived of genetic studies by Sanger targeted to MEN1 gene from a strict number of MEN1 phenocopies. Objectives: to recognize strong clinical profiles capable of predicting the occurrence or absence of germline MEN1 mutation refining the clinical differentiation of phenocopies and mutation-positive cases before genetic testing disclosure. Casuistic/Methods: 143 MEN1 index cases: 87 MEN1-positive and 56 true MEN1 phenocopies (excluded mutations for MLPA assay and by a mini-painel based on long-range PCR and next generation sequencing of 6 MEN1-related genes (MEN1, p15, p18, p21, p27, AIP) covering full coding and non-coding regions. Results: High detectability rate of MEN1 mutation was associated with the presence of ≥ 4 organs affected for primary tumors (100%), association of HPT/PET (neuroendocrine pancreatic tumor)/PIT (93%), HPT/PET (81%), positive familial history (88% vs. 48%), presence of PET (84%) as malign (80%) as multifocal (95%), two different PETs (100%), multiglandular HPT (81%) and diagnosis of one MEN1-related tumor (93%) or of two/three MEN1 tumors diagnosed before 21y (100%). The combination HPT/PIT has the lowest rate of detection of mutation (33%), it is even lower if PIT was acromegaly (12%) or age at the diagnosis of HPT and PIT was, respectively, &gt; 45y and &gt;30y (8%) and absent if it is added uniglandular HPT (0%) or if there was association HPT/PIT (age-independent) with uniglandular HPT (0%). The prediction for detection of mutation increases if these HPT (&gt; 45y)/PIT (&gt; 30y) cases have multiglandular HPT (20%) and it is 100% with association HPT (&lt; 30y)/PIT (&lt; 21y). A p &lt;0.05 was observed to all data above. Conclusions: By integration of phenotypic clues and full genetic analysis applied to the largest MEN1 phenocopy series, we identified strong clinical predictors capable of anticipate the potential risk rate for mutation detection revealing the estimated chance of an index case harbor a mutation or be classified as phenocopy. By their peculiarities, the management/treatment of phenocopies should potentially be different of that recommended to mutation-positive cases.
Functional Characterization of the Orphan Nuclear Receptor TLX in Triple Negative Breast Cancer
Authors: Nelson Adam , Wang Yu , Ma Liqian , He Sisi , Henn Madeline , Shahoei Sayyed Hamed , Saleh Tareq , Carpenter Valerie , Gewirtz David , Spinella Michael J , Nelson Erik Russell 
Published: May 2021

Abstract
Despite the development of various therapeutic strategies, breast cancer persists as the second leading cause of cancer-related death among women in the United States. While endocrine modulation and monoclonal antibody therapy have proved to be indispensable modes of intervention for hormone receptor (HR)-positive and HER-2 positive patients, the triple negative breast cancer (TNBC) patient population do not respond to these therapies. As TNBC is considered one of the most challenging subtypes of breast cancer to treat, there is a significant need for the development of targeted therapeutics. Due to their well-known amenability to small-molecule modulation, we investigated whether any nuclear receptors beyond those that are traditionally studied in breast cancer (e.g. ER, PR, and AR), may represent a novel target in the TNBC patient population. Analysis of clinical data revealed that expression of the orphan nuclear receptor TLX (NR2E1) was positively correlated with relapse-free survival, distant metastasis-free survival, and overall survival in both ER-negative and basal-like breast cancer patients. Therefore, we hypothesized that TLX could influence the pathophysiology of TNBC. To interrogate this hypothesis, we established TNBC cells with stable expression of TLX in order to identify direct regulatory targets, as well as the precise physiological mechanism(s) TLX may be regulating. To date, our work has revealed that TLX inhibits proliferation, slows migration, alters chemosensitivity, and impairs cell cycle progression in TNBC cells. In agreement with these findings, our work has also revealed that TLX is capable of modulating the expression of several genes that are known to regulate the processes of growth, migration, and cell cycle. Taken together, our early work supports our hypothesis, and provides valuable insight into the potential pro-survival function of TLX in TNBC. Ongoing work will continue to probe the mechanisms by which TLX impacts breast cancer biology, and establish whether the growth-inhibitory effects translate to in vivo models. As prior work has demonstrated that TLX’s transcriptional activity can be regulated by both synthetic and natural ligands, the results of our work would provide the foundational data necessary for the development of a TLX-based therapy for a patient population with limited therapeutic options and a poor prognostic outlook.
A Multifocal Paraganglioma in an African Male Due to an Underlying SDHB Mutation
Authors: Siddiqui Nida Mishraz , Seedat Faheem , Bulbulia Saajidah , Krause Amanda , Daya Reyna , Bayat Zaheer 
Published: May 2021

Abstract
Pheochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumors arising from adrenal and extra-adrenal paraganglia. Up to forty percent are due to an underlying germline mutation. Mutations in the subunit B gene of the SDH complex (SDHB) are associated with PGL syndrome four. A 34-yr-old African man from Southern Africa presented with a two-year history of sustained hypertension associated with the classic triad of sweating, headaches and palpitations. Family history was contributory towards early unexpected deaths of his father (age 42) and two younger brothers (ages 13 and 14 respectively). On examination his blood pressure was persistently elevated measuring 146/87mmHg. In view of the classic presenting symptoms and hypertension onset at a young age, a PPGL was suspected. Biochemical investigations were positive with an elevated 24-hour urine normetanephrine level of 35807 (480-2424nmol/24hours), normal metanephrine level of 689 (264-1729nmol/24hours), an elevated normetanephrine:creatinine ratio of 3270 (28-158nmol/mmol creatinine) and an elevated methoxytyramine level 4941.69nmol/24 hours (&lt;800nmol/24 hours). Computed tomography of the abdomen and neck revealed a homogenous soft tissue mass measuring 5.9cm x 3.6cm x 6.6cm anterior to the right kidney and separate from the right adrenal gland and a carotid body tumor measuring 3.6cm x 2.9cm x 4.1cm. Both were radio-avid on a [68Gallium]-DOTATATE-Positron Emission Tomography (PET)-CT. There were no features to suggest metastatic disease. Genetic testing is not available in South Africa; therefore, testing was done at an international laboratory. This revealed a pathological SDHB mutation variant, c.724C&gt;A p.(Arg242Ser) and hence PGL4 syndrome. The patient underwent staged surgery with successful removal of the intra-abdominal tumor. Unfortunately, due to peri-operative complications associated with the second surgery, the patient demised. Histopathological examination of both tumors was consistent with a paraganglioma. Genetic counselling and testing were offered to all living first-degree relatives. His sister tested positive for the same pathological variant. His 6-week-old son will be offered counselling and testing at a later stage. To the best of our knowledge, we are the first to describe the missense SDHB mutation (pathogenic variant c.724C&gt;A p.[Arg242Ser]) and the occurrence of an SDHB associated PGL in a family of African ethnicity. This case highlights the importance of genetic counselling and testing in patients with a confirmed PPGL. Due to resource limitation the African population remains under represented in genetic studies which limits the utility of precision medicine in this group. As such, our case is an important addition to the body of knowledge in this growing field and highlights the need for cost effective genetic screening tools in low resourced settings.
Hormonal Regulation of Semaphorin 7a Promotes Therapeutic Resistance in Breast Cancer
Authors: Crump Lyndsey , Richer Jennifer K , Porter Weston , Lyons Traci 
Published: May 2021

Abstract
Background: The majority of all breast cancers (BC) are estrogen receptor positive (ER+). While ER-targeting endocrine therapies have improved patient survival, many of these tumors develop drug resistance and recur within 20 years. Therefore, novel targets are needed to predict for recurrence and to treat recurrent ER+BC. Previous reports describe a tumor-promotional role for Semaphorin 7A (SEMA7A) in ER- disease; yet, the role of SEMA7A in ER+ disease is poorly characterized. Hypothesis: SEMA7A promotes cell survival and drug resistance in ER+ BC. Methods: We overexpressed SEMA7A in ER+ BC cells, then used the ER-targeting agents tamoxifen and fulvestrant to test how SEMA7A-expressing cells respond to endocrine therapy. In vitro, we used proliferation and cell survival assays. In vivo, we implanted ER+ BC cells, then treated the animals with fulvestrant to measure how SEMA7A affects tumor growth and metastasis. We also utilized drug resistant cells, which have high endogenous SEMA7A levels, to measure markers of stemness and multi-drug resistance via flow cytometry. Results: We first found that SEMA7A expression correlates with decreased relapse free survival in patients with ER+BC who received endocrine therapy (Kmplotter; p=0.042). We also observe that SEMA7A is hormonally regulated in ER+BC, but its expression does not uniformly decrease with endocrine therapy agents. Instead, long term estrogen deprivation and ER-targeting drug treatments increase SEMA7A expression, likely through the action of other hormone receptors such as the androgen receptor, which also increases with long term estrogen deprivation. Further, in ER+ cell lines, overexpression of SEMA7A promotes in vitro growth in the face of estrogen-deprivation, tamoxifen, or fulvestrant treatments. In vivo, SEMA7A promotes fulvestrant resistance in the primary tumor and induces lung metastases. Finally, we report that pro-survival signaling is a therapeutic vulnerability of ER+SEMA7A+ tumors. Conclusion: These studies describe that SEMA7A promotes drug resistance in ER+ BC. We propose that targeting pro-survival signaling may prove efficacious for treating SEMA7A+ tumors, which are less likely to respond to endocrine therapies.
Incidence and Phenotypes of Endocrinopathies in Association With Immune Checkpoint Inhibitors: The Experience of Integrated Health Network
Authors: Mehmood Hassan , Hasan Farhad 
Published: May 2021

Abstract
Introduction: Since 2011 FDA has approved several immune checkpoint inhibitors (ICI) as antineoplastic agents with very promising results. The side effects profile of ICI is different from that of conventional cancer therapies and predominated by immune-related adverse effects (IRAEs). Autoimmune endocrinopathies (AEs), such as disorders of the thyroid, pituitary, and adrenal glands are increasingly recognized IRAEs of ICI. If not diagnosed and treated early, AEs may cause serious harm in an already compromised patient by advanced malignancy. Therefore, it is necessary to recognize the incidence, phenotypes, and time to onset of various AEs in association with ICI. This retrospective study of a large cancer population treated at an integrated health network aims to do so. Methods: We conducted a retrospective chart review of adult patients treated with ICI as cancer therapy at Allegheny Health Network—a major healthcare provider in Western Pennsylvania—between 1/1/2016 and 6/30/2019. Inclusion criteria were ages 18-90 years who received one or more ICI within the study period, laboratory data available for a minimum of 6 months from date of the first ICI dose, and no pre-existing outcome of interest at the time of, or prior to, receiving the first ICI dose. Exclusion criteria were pre-existing thyroid, pituitary, or adrenal diseases. Results: We screened the records of 1200 patients who were treated for 47 different cancers for AEs. Of this sample, 57% were males 92.5% were White. Follow up period ranged between 6-57 months, during which 56% of patient died at a mean age of 67.1 years. The most common cancer diagnoses were non-small cell lung cancer (45.4%), malignant melanoma (11.7%), renal cell carcinoma (6.3%), and small cell lung cancer (6.2%). These patients received one or more agents from the three classes of ICI, including PD-1 (75.86%), PDL-1 (12.57%), and CTLA-4 (11.57%). The overall incidence of AEs was 18%. The distribution of AEs was as follows: primary hypothyroidism 15.3%, secondary hypothyroidism 0.5%, primary hyperthyroidism 3.5%, primary adrenal insufficiency 0.2%, secondary adrenal insufficiency 2.7%, and type 1 diabetes mellitus 0.2%. Of the 42 patients diagnosed with hyperthyroidism, 28 (66.7%) later developed primary hypothyroidism within a mean time of 9 weeks. There was no statistically significant association between the incidence of AEs and gender (P=0.748) or age (P=0.998). Conclusion: AEs are common sequelae of ICI and primary hypothyroidism is the most prevalent AEs among our study sample. This study should help increase awareness about the importance of routine screening of the AEs in cancer patients receiving ICI.
Inhibiting Growth of Human Triple-Negative Breast Cancer Cells by Activating Mutant p53 Protein Alone or in Combination With a Phosphatidylserine-Targeting Antibody
Authors: Liang Yayun , Brekken Rolf A , Hyder Salman M 
Published: May 2021

Abstract
Triple-negative human breast cancers (TNBC) lack three proteins commonly targeted by chemotherapy; estrogen and progesterone receptors, and her-2-neu. Most current protocols used to treat TNBC are largely ineffective and aggressive tumors frequently re-emerge, leading to metastasis and patient death. Thus, new therapies for TNBC are needed. Recent studies show that around 80% of TNBC express mutant p53 (mtp53), a functionally defective form of the p53 tumor suppressor protein. If mtp53 is converted into the active wild-type protein (wtp53), tumor suppressor functions are recovered. Most p53 mutations occur in the DNA-binding domain, causing normal regulation of p53 target genes involved in apoptosis, cell-cycle arrest, and angiogenesis to be blocked. This promotes metastasis and renders tumors resistant to chemotherapy. APR-246 is a small-molecule drug that re-activates mtp53 by covalent modification of the DNA-binding core domain of the mutant protein through alkylation of thiol groups and has been shown to reactivate mtp53 and restore p53 function. We examined whether APR-246 could inhibit TNBC growth, both in vitro and in vivo. Cell viability assays and FACS were used to measure in vitro TNBC cell growth and apoptosis respectively, in MDA-MB-231 and MDA-MB-468 cells, with MCF-7 cells (which express wtp53) as controls. Analysis of TNBC growth in vivo was assessed in a mouse model of MDA-MB-231 derived xenografts. Nuclear extracts of APR-246-treated TNBC cells exhibited significantly increased p53 DNA binding compared with untreated cells, indicating that APR-246 converts mtp53 to wtp53 in these cells. APR-246 significantly reduced TNBC cell viability in vitro, but had no effect on normal mammary cells or wtp53-expressing MCF-7 cells. Pro-apoptotic proteins, Bax, p21 and caspase-3 were elevated in APR-246 treated cells, while the cell survival protein Bcl-2 was suppressed. In the xenograft model, animals were given an intravenous (iv) tail vein injection of APR-246 alone (100 mg/kg/day) once tumors reached 100 mm3. A second group received an intraperitoneal (ip) injection of 2aG4 antibody (100 µg/mouse/day), which targets phosphatidylserine and disrupts tumor blood vessel formation. A third group was given both APR-246 and 2aG4 using the same doses above. A control group received antibody C44 (100 µg/mouse/day, ip) and/or PBS (0.1 mL/day, iv). A total of 18 treatments were used. Administration of APR-246 alone or in combination with 2aG4, significantly reduced TNBC tumor growth, as well as two markers of angiogenesis (vascular endothelial growth factor expression and blood-vessel density). APR-246 in combination with 2aG4 completely eradicated almost 20% of the TNBC tumors. We conclude that TNBC is inhibited by APR-246 and 2aG4. Such treatment could represent an effective and innovative means of combating these particularly aggressive and deadly types of cancer.