Rewired m6A epitranscriptomic networks link mutant p53 to neoplastic transformation.

N6-methyladenosine (m6A), one of the most prevalent mRNA modifications in eukaryotes, plays a critical role in modulating both biological and pathological processes. However, it is unknown whether mutant p53 neomorphic oncogenic functions exploit dysregulation of m6A epitranscriptomic networks. Here, we investigate Li-Fraumeni syndrome (LFS)-associated neoplastic transformation driven by mutant p53 in iPSC-derived astrocytes, the cell-of-origin of gliomas. We find that mutant p53 but not wild-type (WT) p53 physically interacts with SVIL to recruit the H3K4me3 methyltransferase MLL1 to activate the expression of m6A reader YTHDF2, culminating in an oncogenic phenotype. Aberrant YTHDF2 upregulation markedly hampers expression of multiple m6A-marked tumor-suppressing transcripts, including CDKN2B and SPOCK2, and induces oncogenic reprogramming. Mutant p53 neoplastic behaviors are significantly impaired by genetic depletion of YTHDF2 or by pharmacological inhibition using MLL1 complex inhibitors. Our study reveals how mutant p53 hijacks epigenetic and epitranscriptomic machinery to initiate gliomagenesis and suggests potential treatment strategies for LFS gliomas.

Preoperative Ultrasound Scoring of Endometriosis by AAGL 2021 Endometriosis Classification Is Concordant with Laparoscopic Surgical Findings and Distinguishes Early from Advanced Stages.

STUDY OBJECTIVE: To compare the accuracy of preoperative ultrasound (US) in predicting the laparoscopically defined 2021 American Association of Gynecologic Laparoscopists (AAGL) Endometriosis Staging. DESIGN: Retrospective multicenter study of patients treated at 3 specialized endometriosis centers. SETTING: Three specialized endometriosis surgical centers in São Paulo (Brazil), Barcelona (Spain), and Avellino (Italy) participated. PATIENTS: A total of 878 patients aged 15 to 45 years with no history of pelvic malignancy underwent laparoscopic (LPS) treatment for suspected endometriosis. INTERVENTIONS: Retrospective review of preoperative transvaginal and transabdominal US (index test) assessed for endometriosis at all sites used in the 2021 AAGL Endometriosis Classification and classified patients into AAGL-US stages 1 to 4. Results were compared with reference-standard LPS (AAGL-LPS) staging. MEASUREMENTS AND MAIN RESULTS: The AAGL-US and AAGL-LPS stage were concordant in 586 cases (66.7%) (weighted kappa [WK] 0.759; intraclass correlation = 0.906), with the highest agreement observed in patients with no endometriosis (n = 70, 75.3% concordance), AAGL-LPS stage 1 (104, 50.7%) and stage 4 disease (358, 88.2%). Endometriosis was most accurately diagnosed in the rectum/sigmoid colon (WK 0.862), bladder (WK 0.911), and ovaries (WK 0.835/0.795 for right/left, respectively) and least accurately diagnosed at superficial peritoneal (WK 0.442), tubal (WK 0.391/0.363 for right/left, respectively), and retrocervical/uterosacral ligament (WK 0.656) sites. CONCLUSION: Sonographic estimation of the 2021 AAGL Endometriosis Staging is greatest in AAGL-LPS stages 1 and 4 and among patients with no endometriosis. US best identifies endometriosis of the ovaries, bladder, and bowel but is more limited for the tubes and superficial peritoneum.

Hereditary retinoblastoma iPSC model reveals aberrant spliceosome function driving bone malignancies.

The RB1 gene is frequently mutated in human cancers but its role in tumorigenesis remains incompletely defined. Using an induced pluripotent stem cell (iPSC) model of hereditary retinoblastoma (RB), we report that the spliceosome is an up-regulated target responding to oncogenic stress in RB1-mutant cells. By investigating transcriptomes and genome occupancies in RB iPSC­derived osteoblasts (OBs), we discover that both E2F3a, which mediates spliceosomal gene expression, and pRB, which antagonizes E2F3a, coregulate more than one-third of spliceosomal genes by cobinding to their promoters or enhancers. Pharmacological inhibition of the spliceosome in RB1-mutant cells leads to global intron retention, decreased cell proliferation, and impaired tumorigenesis. Tumor specimen studies and genome-wide TCGA (The Cancer Genome Atlas) expression profile analyses support the clinical relevance of pRB and E2F3a in modulating spliceosomal gene expression in multiple cancer types including osteosarcoma (OS). High levels of pRB/E2F3a­regulated spliceosomal genes are associated with poor OS patient survival. Collectively, these findings reveal an undiscovered connection between pRB, E2F3a, the spliceosome, and tumorigenesis, pointing to the spliceosomal machinery as a potentially widespread therapeutic vulnerability of pRB-deficient cancers.

Surgical Techniques to Optimize Ovarian Reserve during Laparoscopic Cystectomy for Ovarian Endometrioma.

Surgical management of ovarian endometrioma in patients desiring fertility is complicated by the need to balance maximal resection of disease with efforts to spare normal ovarian cortex. Optimization of tubal anatomy is another frequent consideration. Fertility-sparing laparoscopic techniques at the time of cystectomy for ovarian endometrioma seek to limit iatrogenic surgical damage to the ovarian cortex and strategically assess and respond to genital tract patency. Surgical candidates frequently desire relief from endometriosis-associated pain while also seeking to optimize spontaneous or assisted conception rates. Operative benefits include potential for surgical and histopathologic diagnosis of endometriosis, evaluation of genital tract patency, and treatment of visualized lesions. Resection of ovarian endometrioma nonetheless poses significant risks, including surgical injury, blood loss, post-surgical decline in ovarian reserve and post-operative inflammation with adhesion formation, both of which may impair folliculogenesis. We present the case of a 32-year-old woman with known endometriosis and continued pain refractory to medical management who opted for surgical management of her disease tailored toward optimizing her chances at future conception. Using this case as an example, we describe techniques and considerations for diagnostic laparoscopy, adhesiolysis, ovarian cystectomy, chromopertubation, and salpingectomy with a focus on maintaining a fertility-preserving approach.

Patient-derived iPSCs link elevated mitochondrial respiratory complex I function to osteosarcoma in Rothmund-Thomson syndrome.

Rothmund-Thomson syndrome (RTS) is an autosomal recessive genetic disorder characterized by poikiloderma, small stature, skeletal anomalies, sparse brows/lashes, cataracts, and predisposition to cancer. Type 2 RTS patients with biallelic RECQL4 pathogenic variants have multiple skeletal anomalies and a significantly increased incidence of osteosarcoma. Here, we generated RTS patient-derived induced pluripotent stem cells (iPSCs) to dissect the pathological signaling leading to RTS patient-associated osteosarcoma. RTS iPSC-derived osteoblasts showed defective osteogenic differentiation and gain of in vitro tumorigenic ability. Transcriptome analysis of RTS osteoblasts validated decreased bone morphogenesis while revealing aberrantly upregulated mitochondrial respiratory complex I gene expression. RTS osteoblast metabolic assays demonstrated elevated mitochondrial respiratory complex I function, increased oxidative phosphorylation (OXPHOS), and increased ATP production. Inhibition of mitochondrial respiratory complex I activity by IACS-010759 selectively suppressed cellular respiration and cell proliferation of RTS osteoblasts. Furthermore, systems analysis of IACS-010759-induced changes in RTS osteoblasts revealed that chemical inhibition of mitochondrial respiratory complex I impaired cell proliferation, induced senescence, and decreased MAPK signaling and cell cycle associated genes, but increased H19 and ribosomal protein genes. In summary, our study suggests that mitochondrial respiratory complex I is a potential therapeutic target for RTS-associated osteosarcoma and provides future insights for clinical treatment strategies.

AAGL 2021 Endometriosis Classification: An Anatomy-based Surgical Complexity Score.

STUDY OBJECTIVE: To develop a new endometriosis classification system for scoring intraoperative surgical complexity and to examine its correlation with patient-reported pain and infertility. DESIGN: Multicenter study of patients treated at 3 recognized endometriosis centers. SETTING: Three specialized endometriosis surgical centers in São Paulo, Brazil and Barcelona, Spain. PATIENTS: Patients aged 15 to 45 years with histologically proven endometriosis and no history of pelvic malignancy underwent laparoscopic treatment of endometriosis. INTERVENTIONS: Demographic data and clinical history, including dysmenorrhea, noncyclic pelvic pain, dyspareunia, dysuria and dyschezia, were prospectively recorded. All patients were staged surgically according to the new 2021 American Association of Gynecologic Laparoscopists (AAGL) and revised American Society of Reproductive Medicine (ASRM) classification systems. The staging for each system was compared against a 4-level surgical complexity scale defined by the most complex procedure performed. MEASUREMENTS AND MAIN RESULTS: A total of 1224 patients undergoing surgery met inclusion criteria. The AAGL score discriminated between 4 stages of surgical complexity with high reproducibility (κ = 0.621), whereas the ASRM score discriminated between the complexity stages with poor reproducibility (κ = 0.317). The AAGL staging system correlated with dysmenorrhea, dyspareunia, dyschezia, total pain score, and infertility comparably with the ASRM staging system. CONCLUSION: The AAGL 2021 Endometriosis Classification allows for identifying objective intraoperative findings that reliably discriminate surgical complexity levels better than the ASRM staging system. The AAGL severity stage correlates comparably with pain and infertility symptoms with the ASRM stage.

Effect of Methotrexate on Salpingostomy Completion Rate for Tubal Ectopic Pregnancy: A Retrospective Cohort Study.

STUDY OBJECTIVE: To determine whether completion rates of salpingostomy for tubal ectopic pregnancy are compromised by initial medical management with methotrexate (MTX). DESIGN: Retrospective cohort study. SETTING: Single academic hospital system. PATIENTS: Patients requiring surgery for ectopic pregnancy between 2006 and 2017. INTERVENTIONS: A subset of patients who went directly to surgery, and all patients who failed MTX before requiring surgery underwent detailed chart review. Salpingostomy plan and success rate and salpingostomy failure reasons were compared between patients pretreated with MTX and those who were MTX-untreated. MEASUREMENTS AND MAIN RESULTS: Among 94 ectopic pregnancies requiring surgery after failed MTX treatment, 55 (59%) underwent planned salpingostomy. From 693 ectopic pregnancies managed without MTX, 166 were analyzed in detail, of which 80 (48%) underwent planned salpingostomy. The patients who underwent planned salpingostomy were thinner (body mass index 27.3 ± 7.2 kg/m2 vs 29.3 ± 8.3 kg/m2; p = .048), less frequently African American (33% vs 47%; p = .017), and more likely to have a visualized adnexal lesion (70% vs 52%; p = .004) than those undergoing planned salpingectomy. Preoperative ultrasound identified fetal cardiac activity and hemoperitoneum at comparable rates. MTX exposure was not associated with age, body mass index, race, ectopic risk factors, human chorionic gonadotropin levels, or gestational age at diagnosis, but the patients treated with MTX underwent surgery later than those who were untreated (gestational age 53.4 ± 11.2 days vs 43.5 ± 11 days; p <.001). The differences between the adnexal lesion size and rates of fetal cardiac activity and hemoperitoneum on ultrasound related to MTX exposure did not meet significance. Planned salpingostomy was completed in 22 (40%) of the patients treated with MTX vs 34 (42%) of those who were untreated. The reasons for failure, surgery time, and rates of hemoperitoneum or ectopic rupture were not associated with MTX exposure. Body mass index, race, tubal anastomosis history, visualization of the adnexal lesion, and MTX exposure were not significantly associated with the salpingostomy rate in a multivariate logistic regression model, but having a subspecialist surgeon (odds ratio 2.70; 95% confidence interval, 1.08-6.76; p = .033) and tubal rupture at surgery (odds ratio 0.23; 95% confidence interval, 0.09-0.54; p = .001) were. CONCLUSION: The initial medical management of an ectopic pregnancy with MTX is not associated with a decreased salpingostomy success rate.

Circulating Myeloid-derived Suppressor Cells Facilitate Invasion of Thyroid Cancer Cells by Repressing miR-486-3p.

BACKGROUND: Myeloid-derived suppressor cells (MDSCs) have become increasingly recognized as facilitators of tumor development. However, the role of MDSCs in papillary thyroid carcinoma (PTC) progression has not been clearly explored. OBJECTIVE: We aimed to evaluate the levels and function of circulating MDSCs in PTC. METHODS: The proportion of circulating polymorphonuclear (PMN)-MDSCs and mononuclear-MDSCs from patients with PTC or benign thyroid nodules and healthy controls was measured using flow cytometry. For immunosuppressive activity analysis, sorted circulating MDSCs were cocultured with CD3/CD28-costimulated T lymphocytes and the proliferation of T cells was determined. PTC cell lines (TPC-1 and BC-PAP) were cocultured with PMN-MDSCs, and the effects on cell migration, invasion, proliferation, and apoptosis were evaluated. The differential expressed microribonucleic acids (RNAs) and messenger RNAs and their function were also explored in TPC-1 cells cocultured with or without PMN-MDSCs. RESULTS: PMN-MDSCs were increased in peripheral blood mononuclear cells of patients with PTC. Circulating PMN-MDSCs displayed strong T cell suppressive activity. PTC cells demonstrated enhanced invasive capabilities in vitro and in vivo when cocultured with sorted PMN-MDSCs. PMN-MDSCs decreased expression of miR-486-3p and activated nuclear factor kappa B2 (NF-κB2), a direct target of miR-486-3p. Rescue of miR-486-3p diminished the cell migration and invasion induced by PMN-MDSCs. CONCLUSION: Collectively, our work indicates that circulating PMN-MDSCs promote PTC progression. By suppressing miR-486-3p, PMN-MDSCs promote the activity of the NF-κB2 signaling pathway, resulting in accelerated invasion of PTC cells, which may provide new therapeutic strategies for treatment of thyroid cancer.

Use of hysteroscopy in diagnosis and follow-up of acquired uterine enhanced myometrial vascularity.

OBJECTIVE: To describe the role of hysteroscopy in diagnosis and subsequent follow-up of uterine enhanced myometrial vascularity (EMV). Uterine EMV, previously known as arteriovenous malformation (AVM), is a rare but cannot-miss finding often associated with prior pregnancy or uterine surgery and is typically suspected when a vascular mass is found on ultrasound. Color Doppler imaging will demonstrate high-velocity, low-impedance flow, with more significant shunts demonstrating higher peak systolic velocity (PSV). If not already diagnosed by ultrasound, accurate recognition during hysteroscopy is mandatory prior to any uterine instrumentation, as biopsy or curettage can lead to unanticipated massive hemorrhage. While many cases of EMV may resolve spontaneously, actively bleeding patients may require treatment with embolization, a procedure that may decrease ovarian reserve and impair fertility, though favorable reproductive outcomes have been reported. Others have reported success with hysteroscopic management using a bipolar electrosurgical loop. DESIGN: Case report. SETTING: Academic hospital system. PATIENT(S): We describe a 22-year-old G2P1011 who presented to the emergency department with heavy vaginal bleeding and a negative urine human chorionic gonadotropin 9 weeks following a first-trimester termination of pregnancy. Her ultrasound demonstrated a heterogeneous 2.6×2.3×2.6 cm vascular mass in the endometrial canal that was initially interpreted as retained products of conception. Unfortunately, PSV in the lesion was not measured. During observation, bleeding continued, and her hemoglobin dropped from 8.3 g/dL to 6.9 g/dL the next morning. She was transfused 2 units of blood and taken to the operating room for hysteroscopic evaluation and possible uterine curettage. INTERVENTION(S): Hysteroscopy revealed a large pulsating 2cm bluish vascular mass that was recognized as a uterine EMV and the procedure was terminated with the plan for embolization. Given fertility concerns, the diagnosis was confirmed with MRI/MRA, which identified a 2.7cm mass-like process with early post-contrast enhancement in the arterial phase. An angiogram demonstrated bilaterally enlarged tortuous uterine arteries perfusing a hypervascular EMV that was treated with selective bilateral uterine artery embolization. MAIN OUTCOME MEASURE(S): Further bleeding or evidence of EMV. RESULT(S): Follow-up office hysteroscopy at 2 weeks demonstrated a 2 cm raised area of tissue without pulsations. At 6 weeks post-procedure, bleeding had ceased, and office hysteroscopy revealed only a small 0.5 cm calcified nodule with a circumferential pseudo-decidual reaction. CONCLUSION(S): Hysteroscopy may be used to diagnose EMV when ultrasound is not conclusive. Recognition of the pulsating vascular appearance of EMV on hysteroscopy is critical in preventing hemorrhage from inappropriate curettage. Resolution of the lesion following embolization can be readily demonstrated with office hysteroscopy.

LncRNA H19 Suppresses Osteosarcomagenesis by Regulating snoRNAs and DNA Repair Protein Complexes.

Osteosarcoma is one of the most frequent common primary malignant tumors in childhood and adolescence. Long non-coding RNAs (lncRNAs) have been reported to regulate the initiation and progression of tumors. However, the exact molecular mechanisms involving lncRNA in osteosarcomagenesis remain largely unknown. Li-Fraumeni syndrome (LFS) is a familial cancer syndrome caused by germline p53 mutation. We investigated the tumor suppressor function of lncRNA H19 in LFS-associated osteosarcoma. Analyzing H19-induced transcriptome alterations in LFS induced pluripotent stem cell (iPSC)-derived osteoblasts, we unexpectedly discovered a large group of snoRNAs whose expression was significantly affected by H19. We identified SNORA7A among the H19-suppressed snoRNAs. SNORA7A restoration impairs H19-mediated osteogenesis and tumor suppression, indicating an oncogenic role of SNORA7A. TCGA analysis indicated that SNORA7A expression is associated with activation of oncogenic signaling and poor survival in cancer patients. Using an optimized streptavidin-binding RNA aptamer designed from H19 lncRNA, we revealed that H19-tethered protein complexes include proteins critical for DNA damage response and repair, confirming H19's tumor suppressor role. In summary, our findings demonstrate a critical role of H19-modulated SNORA7A expression in LFS-associated osteosarcomas.

Genomic Integrity Safeguards Self-Renewal in Embryonic Stem Cells.

A multitude of signals are coordinated to maintain self-renewal in embryonic stem cells (ESCs). To unravel the essential internal and external signals required for sustaining the ESC state, we expand upon a set of ESC pluripotency-associated phosphoregulators (PRs) identified previously by short hairpin RNA (shRNA) screening. In addition to the previously described Aurka, we identify 4 additional PRs (Bub1b, Chek1, Ppm1g, and Ppp2r1b) whose depletion compromises self-renewal and leads to consequent differentiation. Global gene expression profiling and computational analyses reveal that knockdown of the 5 PRs leads to DNA damage/genome instability, activating p53 and culminating in ESC differentiation. Similarly, depletion of genome integrity-associated genes involved in DNA replication and checkpoint, mRNA processing, and Charcot-Marie-Tooth disease lead to compromise of ESC self-renewal via an increase in p53 activity. Our studies demonstrate an essential link between genomic integrity and developmental cell fate regulation in ESCs.

Immunomodulatory TGF-ß Signaling in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is an inflammation-induced and chemotherapy-resistant cancer. Dysregulated signaling in the transforming growth factor beta (TGF-ß) pathway plays a central role in inflammation, fibrogenesis, and immunomodulation in the HCC microenvironment. This review dissects the genetic landscape of the TGF-ß superfamily genes in HCC and discusses the essential effects of this pathway on the tumor immune microenvironment. We highlight the TGF-ß signature as a potential biomarker for identifying individualized immunotherapeutic approaches in HCC. An improved understanding of the detailed mechanisms of liver cancer immunogenicity and the specific role of TGF-ß in mediating immunotherapy resistance in HCC will provide important insights into HCC immune escape and promote the development of biomarker-derived combination immunotherapies for HCC.

Perioperative Interventions to Minimize Blood Loss at the Time of Hysterectomy for Uterine Leiomyomas: A Systematic Review and Meta-analysis.

STUDY OBJECTIVE: Hysterectomy for uterine leiomyoma(s) is associated with significant morbidity including blood loss. A systematic review and meta-analysis was conducted to identify nonhormonal interventions, perioperative surgical interventions, and devices to minimize blood loss at the time of hysterectomy for leiomyoma. DATA SOURCES: Librarian-led search of Embase, MEDLINE, Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Cochrane databases from 1946 to 2018 with hand-guided updates. METHODS OF STUDY SELECTION: Included studies reported on keywords of hysterectomy, leiomyoma, and operative blood loss/postoperative hemorrhage/uterine bleeding/metrorrhagia/hematoma. The review excluded a comparison of route of hysterectomy, morcellation, vaginal cuff closure, hormonal medications, vessel sealing devices for vaginal hysterectomy, and case series with <10 patients. TABULATION, INTEGRATION, AND RESULTS: Surgical blood loss, postoperative hemoglobin (Hb) drop, hemorrhage, transfusion, and major and minor complications were analyzed and aggregated in meta-analyses for comparable studies in each category. A total of 2016 unique studies were identified, 33 of which met the inclusion criteria, and 22 were used for quantitative synthesis. The perioperative use of misoprostol in abdominal hysterectomy (AH) was associated with a lower postoperative Hb drop (0.59 g/dL; 95% confidence interval [CI], 0.39-0.79; p < .01) and blood loss (-96.43 mL; 95% CI, -153.52 to -39.34; p < .01) compared with placebo. Securing the uterine vessels at their origin in laparoscopic hysterectomy (LH) was associated with decreased intraoperative blood loss (-69.07 mL; 95% CI, -135.20 to -2.95; p = .04) but no significant change in postoperative Hb (0.24 g/dL; 95% CI, -0.31 to 0.78; p = .39) compared with securing them by the uterine isthmus. Uterine artery ligation in LH before dissecting the ovarian/utero-ovarian vessels was associated with lower surgical blood loss compared with standard ligation (-27.72 mL; 95% CI, -35.07 to -20.38; p < .01). The postoperative Hb drop was not significantly different with a bipolar electrosurgical device versus suturing in AH (0.26 g/dL; 95% CI, -0.19 to 0.71; p = .26). There was no significant difference between an electrosurgical bipolar vessel sealer (EBVS) and conventional bipolar electrosurgical devices in the Hb drop (0.02 g/dL; 95% CI, -0.15 to 0.20; p = .79) or blood loss (-50.88 mL; 95% CI, -106.44 to 4.68; p = .07) in LH. Blood loss in LH was not decreased with the LigaSure (Medtronic, Minneapolis, MN) impedance monitoring EBVS compared with competing EBVS systems monitoring impedance or temperature (2.00 mL; 95% CI, -8.09 to 12.09; p = .70). No significant differences in hemorrhage, transfusion, or major complications were noted for all interventions. CONCLUSION: Perioperative misoprostol in AH led to a reduction in surgical blood loss and postoperative Hb drop (moderate level of evidence by Grading of Recommendations, Assessment, Development and Evaluation guidelines) although the clinical benefit is likely limited. Remaining interventions, although promising, had at best low-quality evidence to support their use at this time. Larger and rigorously designed randomized trials are needed to establish the optimal set of perioperative interventions for use in hysterectomy for leiomyomas.

Generation of a heterozygous p53 R249S mutant human embryonic stem cell line by TALEN-mediated genome editing.

As one of the most essential genome guardians, p53 and its mutants have been suggested associated with many types of cancers. Many p53 mutants function induce unique phenotypes, including carcinogenesis, metastasis, and drug resistance. The p53(R249S) mutation is the most prevalent and specific mutation associated with liver cancer development. Here, we demonstrate the generation of a heterozygous p53(R249S) mutation in the H9 human embryonic stem cell line using TALEN-mediated genome editing. The generated cell line maintains a normal karyotype, a pluripotent state and the in vivo capacity to develop a teratoma containing all three germ layer tissues.

Induced Pluripotent Stem Cells and Induced Pluripotent Cancer Cells in Cancer Disease Modeling.

In 2006, Noble Prize laureate Shinya Yamanaka discovered that a set of transcription factors can reprogram terminally differentiated somatic cells to a pluripotent stem cell state. Since then, induced pluripotent stem cells (iPSCs) have come into the public spotlight. Amidst a growing field of promising clinical uses of iPSCs in recent years, cancer disease modeling has emerged as a particularly promising and rapidly translatable application of iPSCs. Technological advances in genome editing over the past few years have facilitated increasingly rapid progress in generation of iPSCs with clearly defined genetic backgrounds to complement existing patient-derived models. Improved protocols for differentiation of iPSCs, engineered iPSCs and embryonic stem cells (ESCs) now permit the study of disease biology in the majority of somatic cell types. Here, we highlight current efforts to create patient-derived iPSC disease models to study various cancer types. We review the advantages and current challenges of using iPSCs in cancer disease modeling.

Modeling Osteosarcoma Using Li-Fraumeni Syndrome Patient-derived Induced Pluripotent Stem Cells.

Li-Fraumeni syndrome (LFS) is an autosomal dominant hereditary cancer disorder. Patients with LFS are predisposed to a various type of tumors, including osteosarcoma--one of the most frequent primary non-hematologic malignancies in the childhood and adolescence. Therefore, LFS provides an ideal model to study this malignancy. Taking advantage of iPSC methodologies, LFS-associated osteosarcoma can be successfully modeled by differentiating LFS patient iPSCs to mesenchymal stem cells (MSCs), and then to osteoblasts--the cells of origin for osteosarcomas. These LFS osteoblasts recapitulate oncogenic properties of osteosarcoma, providing an attractive model system for delineating the pathogenesis of osteosarcoma. This manuscript demonstrates a protocol for the generation of iPSCs from LFS patient fibroblasts, differentiation of iPSCs to MSCs, differentiation of MSCs to osteoblasts, and in vivo tumorigenesis using LFS osteoblasts. This iPSC disease model can be extended to identify potential biomarkers or therapeutic targets for LFS-associated osteosarcoma.

Cancer in a dish: progress using stem cells as a platform for cancer research.

Cancer models derived from patient specimens poorly reflect early-stage cancer development because cancer cells acquire numerous additional molecular alterations before the disease is clinically detectable. Earlier studies have used differentiated cells derived from induced pluripotent cancer cells (iPCCs) to partially mirror cancer disease phenotype, but the highly heterogeneous nature of cancer cells as well as difficulties with reprogramming cancer cells has limited the application of this technique. An alternative approach to modeling cancer in a dish entails reprogramming adult differentiated cells from patients with cancer syndromes to pluripotent stem cells (PSCs), followed by directed differentiation of those PSCs. A directed reprogramming and differentiation strategy has the potential to recapitulate cancer progression and capture the earliest molecular alterations that underlie cancer initiation. The reprogrammed cells share patient-specific genetic and epigenetic traits, offering a new platform to develop personalized therapy for cancer patients. In this review, we will provide an overview of available reprogramming methods of cancer cells and describe how cancer-derived stem cells have been used to characterize effects of defined molecular alterations in specific cell types. We also describe the "disease in a dish" model developed to study genetic cancer syndromes. These approaches highlight recent contributions of stem cell technology to the cancer biology realm.

Establishment of a human embryonic stem cell line with homozygous TP53 R248W mutant by TALEN mediated gene editing.

Genetic mutations in TP53 contribute to multiple human cancers. Here we report the generation of a H1-p53(R248W/R248W) human embryonic stem cell line harboring a homozygous TP53 R248W mutation created by TALEN-mediated precise gene editing. The H1-p53(R248W/R248W) cell line maintains a normal karyotype, robust pluripotency gene expression, and the potential to differentiate to the three germ layers.

Genomic Profiling and Metabolic Homeostasis in Primary Liver Cancers.

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA), the two most common primary liver cancers, represent the second most common cancer-related cause of death worldwide, with most cases being diagnosed at an advanced stage. Recent genome-wide studies have helped to elucidate the molecular pathogenesis and genetic heterogeneity of liver cancers. This review of the genetic landscape of HCC and iCCA discusses the most recent findings from genomic profiling and the current understanding of the pathways involved in the initiation and progression of liver cancer. We highlight recent insights gained from metabolic profiling of HCC and iCCA. This knowledge will be key to developing clinically useful diagnostic/prognostic profiles, building targeted molecular and immunologic therapies, and ultimately curing these complex and heterogeneous diseases.

Minimally Invasive Approaches to Myoma Management.

Patients affected by the presence of leiomyomas may incur a substantial physical, emotional, social, and financial toll as well as losses in their quality of life. Although many myomas are not amenable to medical therapy or hysteroscopic resection, many others are amenable to minimally invasive surgical approaches. In patients who prefer to retain their fertility, laparoscopic myomectomy should be considered the intervention of choice. In this review, we expand on the surgical techniques of both conventional laparoscopic and robotic-assisted myomectomies. We discuss port placement, enucleation of myomas, tissue extraction, minimization of blood loss, adhesion prevention, and the technique for closure of uterine incisions. Finally, we discuss the available data supporting the use of these 2 approaches as the preferred, safe, and effective fertility-sparing surgical option. We also briefly discuss the emerging technologies of uterine artery embolization, ultrasound surgery, and radiofrequency ablation.