Paneth-like cells produced from OLFM4 stem cells support OLFM4 stem cell growth in advanced colorectal cancer.

Tumor tissues consist of heterogeneous cells that originate from stem cells; however, their cell fate determination program remains incompletely understood. Using patient-derived organoids established from patients with advanced colorectal cancer (CRC), we evaluated the potential of olfactomedin 4 (OLFM4) stem cells to produce a bifurcated lineage of progenies with absorptive and secretory properties. In the early phases of organoid reconstruction, OLFM4 cells preferentially gave rise to secretory cells.

Integration of human inspection and artificial intelligence-based morphological typing of patient-derived organoids reveals interpatient heterogeneity of colorectal cancer.

Colorectal cancer (CRC) is a heterogenous disease, and patients have differences in therapeutic response. However, the mechanisms underlying interpatient heterogeneity in the response to chemotherapeutic agents remain to be elucidated, and molecular tumor characteristics are required to select patients for specific therapies. Patient-derived organoids (PDOs) established from CRCs recapitulate various biological characteristics of tumor tissues, including cellular heterogeneity and the response to chemotherapy.

A protocol for efficient CRISPR-Cas9-mediated knock-in in colorectal cancer patient-derived organoids.

Patient-derived organoids (PDOs) recapitulate the cellular heterogeneity of the original colorectal tumor tissue. Here, we describe a protocol to generate genetically modified PDOs to investigate cancer stem cells. This protocol uses the CRISPR-Cas9 system to knock-in the IRES-EGFP-P2A-iCaspase9 cassette into the 3' UTR of the potential cancer stem cell marker gene, which allows us to investigate their potential for self-replication and pluripotency.

Comparative Analysis of Patient-Matched PDOs Revealed a Reduction in OLFM4-Associated Clusters in Metastatic Lesions in Colorectal Cancer.

Metastasis is the major cause of cancer-related death, but whether metastatic lesions exhibit the same cellular composition as primary tumors has yet to be elucidated. To investigate the cellular heterogeneity of metastatic colorectal cancer (CRC), we established 72 patient-derived organoids (PDOs) from 21 patients. Combined bulk transcriptomic and single-cell RNA-sequencing analysis revealed decreased gene expression of markers for differentiated cells in PDOs derived from metastatic lesions.

Evaluation of the RAS signaling network in response to MEK inhibition using organoids derived from a familial adenomatous polyposis patient.

RAS signaling is a promising target for colorectal cancer (CRC) therapy, and a variety of selective inhibitors have been developed. However, their use has often failed to demonstrate a significant benefit in CRC patients. Here, we used patient-derived organoids (PDOs) derived from a familial adenomatous polyposis (FAP) patient to analyze the response to chemotherapeutic agents targeting EGFR, BRAF and MEK.

IFN/STAT signaling controls tumorigenesis and the drug response in colorectal cancer.

Colorectal cancer (CRC) is caused by genetic alterations, and comprehensive sequence analyses have revealed the mutation landscapes. In addition to somatic changes, genetic variations are considered important factors contributing to tumor development; however, our knowledge on this subject is limited. Familial adenomatous polyposis coli (FAP) is an autosomal-dominant inherited disease caused by germline mutations in the adenomatous polyposis coli (APC) gene.

Targeted disruption of FSCN2 gene induces retinopathy in mice.

Purpose: To investigate the morphology and function of photoreceptors in mice with mutation of the FSCN2 gene.

Methods: A mouse line was generated carrying the 208delG mutation (point mutation, or p-type) and another with replacement of exon 1 by the cDNA of a green fluorescent protein (GFP knock-in, or g-type). The expression of retinal mRNA was determined by reverse transcription (RT)-polymerase chain reaction (PCR) and in situ hybridization performed on retinal sections.

Lack of acrosome formation in mice lacking a Golgi protein, GOPC.

The acrosome is a unique organelle that plays an important role at the site of sperm-zona pellucida binding during the fertilization process, and is lost in globozoospermia, an inherited infertility syndrome in humans. Although the acrosome is known to be derived from the Golgi apparatus, molecular mechanisms underlying acrosome formation are largely unknown. Here we show that Golgi-associated PDZ- and coiled-coil motif-containing protein (GOPC), a recently identified Golgi-associated protein, is predominantly localized at the trans-Golgi region in round spermatids, and male mice in which GOPC has been disrupted are infertile with globozoospermia.

Altered water barrier function in epidermal-type fatty acid binding protein-deficient mice.

We have generated mutant mice for epidermal-type fatty acid binding protein by the gene targeting technique and examined the phenotype in detail. Despite a lack in the expression of epidermal-type fatty acid binding protein mRNA and its protein in the skin and other tissues of the mutant mice, the animals appeared normal in gross and histologic examination. Northern blot analysis of other fatty acid binding proteins revealed a distinct elevated gene expression of heart-type fatty acid binding protein in the skin of the homozygous mice.