BRG1 establishes the neuroectodermal chromatin landscape to restrict dorsal cell fates.

Cell fate decisions are achieved with gene expression changes driven by lineage-specific transcription factors (TFs). These TFs depend on chromatin remodelers including the Brahma-related gene 1 (BRG1)-associated factor (BAF) complex to activate target genes. BAF complex subunits are essential for development and frequently mutated in cancer.

A pan-cancer organoid platform for precision medicine.

Patient-derived tumor organoids (TOs) are emerging as high-fidelity models to study cancer biology and develop novel precision medicine therapeutics. However, utilizing TOs for systems-biology-based approaches has been limited by a lack of scalable and reproducible methods to develop and profile these models. We describe a robust pan-cancer TO platform with chemically defined media optimized on cultures acquired from over 1,000 patients.

Tumor suppressor SMARCB1 suppresses super-enhancers to govern hESC lineage determination.

The SWI/SNF complex is a critical regulator of pluripotency in human embryonic stem cells (hESCs), and individual subunits have varied and specific roles during development and in diseases. The core subunit SMARCB1 is required for early embryonic survival, and mutations can give rise to atypical teratoid/rhabdoid tumors (AT/RTs) in the pediatric central nervous system. We report that in contrast to other studied systems, SMARCB1 represses bivalent genes in hESCs and antagonizes chromatin accessibility at super-enhancers.

MiRNA-Mediated Regulation of the SWI/SNF Chromatin Remodeling Complex Controls Pluripotency and Endodermal Differentiation in Human ESCs.

MicroRNAs and chromatin remodeling complexes represent powerful epigenetic mechanisms that regulate the pluripotent state. miR-302 is a strong inducer of pluripotency, which is characterized by a distinct chromatin architecture. This suggests that miR-302 regulates global chromatin structure; however, a direct relationship between miR-302 and chromatin remodelers has not been established.

Cleft Palate in a Mouse Model of SOX2 Haploinsufficiency.

Objective: While SEX-determining region Y-Box 2 (SOX2) mutations are typically recognized as yielding ocular and central nervous system abnormalities, they have also been associated with other craniofacial defects. To elucidate the genesis of the latter, Sox2 hypomorphic (Sox2(HYP)) mice were examined, with particular attention to secondary palatal development.

Results: Clefts of the secondary palate were found to be highly penetrant in Sox2(HYP) mice.

SOX2 maintains the quiescent progenitor cell state of postnatal retinal Muller glia.

Within discrete regions of the developing mammalian central nervous system, small subsets of glia become specialized to function as neural stem cells. As a result of their self-renewal and neurogenic capacity, these cells later serve to replenish neurons and glia during persistent or injury-induced adult neurogenesis. SOX2, an HMG box transcription factor, plays an essential role in the maintenance of both embryonic and adult neural progenitors.

SOX2 hypomorphism disrupts development of the prechordal floor and optic cup.

Haploinsufficiency for the HMG-box transcription factor SOX2 results in abnormalities of the human ventral forebrain and its derivative structures. These defects include anophthalmia (absence of eye), microphthalmia (small eye) and hypothalamic hamartoma (HH), an overgrowth of the ventral hypothalamus. To determine how Sox2 deficiency affects the morphogenesis of the ventral diencephalon and eye, we generated a Sox2 allelic series (Sox2(IR), Sox2(LP), and Sox2(EGFP)), allowing for the generation of mice that express germline hypomorphic levels (<40%) of SOX2 protein and that faithfully recapitulate SOX2 haploinsufficient human phenotypes.

Current immunotherapeutic strategies in colon cancer.

Because chemotherapy is standard in the treatment of colorectal cancer, it is important to demonstrate whether immunizations may be given to patients receiving systemic chemotherapy. Although some studies have demonstrated immune responses in patients with metastatic colorectal carcinoma who failed standard chemotherapy, the setting of minimal residual disease may be the preferred setting for cancer vaccines. It may be important to choose antigens that have functions important to the cancer cell.

Update on anti-CTLA-4 antibodies in clinical trials.

Breaking immune tolerance against tumor self-antigens is presently an area of intense research in the design of cancer therapies. One possible method to enhance immune system activation against tumor antigens is by blocking the inhibitory co-stimulatory signals mediated by cytotoxic T lymphocyte antigen 4, (CTLA-4) expressed on activated T cells. The fully human monoclonal antibodies that are directed against human CTLA-4, ipilimumab (Medarex/Bristol-Myers Squibb) and CP-675,206 (Pfizer/Abgenix, now Amgen), have demonstrated activity against metastatic melanoma, hormone refractory prostate cancer and other malignancies.