The single-stranded DNA-binding factor SUB1/PC4 alleviates replication stress at telomeres and is a vulnerability of ALT cancer cells.

To achieve replicative immortality, cancer cells must activate telomere maintenance mechanisms. In 10 to 15% of cancers, this is enabled by recombination-based alternative lengthening of telomeres pathways (ALT). ALT cells display several hallmarks including heterogeneous telomere length, extrachromosomal telomeric repeats, and ALT-associated PML bodies.

A mechanism for telomere-specific telomere length regulation.

Telomeric DNA, composed of short, direct repeats, is of crucial importance for chromosome stability. Due to intrinsic problems with replicating this DNA, the repeat tracts shorten at each cell division. Once repeat tracts become critically short, a telomeric stress signal induces cellular senescence and division arrest, which eventually may lead to devastating age-related degenerative diseases associated with dysfunctional telomers.

The coculture of in vitro produced porcine embryos and oviductal epithelial cells improves blastocyst formation and modify embryo quality.

The efficiency of in vitro embryo production in mammals is influenced by variables associated with culture conditions during maturation, fertilization, and embryonic development. The embryos obtained often exhibit low quality due to suboptimal in vitro culture conditions compared to the in vivo environment. Co-culturing gametes and embryos with somatic cells has been developed to enhance in vitro culture conditions.

Effects of the addition of insulin-transferrin-selenium (ITS) and/or metformin to the maturation of porcine oocytes on cytoplasmic maturation and embryo development.

Context: One of the main problems of porcine in vitro maturation (IVM) is incomplete cytoplasmatic maturation. Nuclear and cytoplasmic maturation will determine the future success of fertilisation and embryo development. Insulin-transferrin-selenium (ITS) has insulin-like and antioxidant effects, and metformin (M) is an insulin-sensitiser and antioxidant drug.

Canine IVM With SOF Medium, Insulin-Transferrin-Selenium, and Low O Tension Improves Oocyte Meiotic Competence and Decreases Reactive Oxygen Species Levels.

Assisted reproductive technologies in canine species are limited due to the low efficiency of maturation (IVM). Unlike other mammals, bitches ovulate oocytes in the germinal vesicle stage and complete metaphase II (MII) after 48-72 h in the oviductal environment and become fertilizable. For this reason, we compared two different IVM media, synthetic oviductal fluid (SOF) supplemented with 8% bovine serum albumin (BSA) or a mixture of 8% BSA-2.

Embryotrophic effect of a short-term embryo coculture with bovine luteal cells.

The coculture with somatic cells is an alternative to improve suboptimal in vitro culture (IVC) conditions and promote embryo development. Several cell types have been used for this purpose, but there is no information about using luteal cells in short-term coculture with embryos. Consequently, this study aimed to assess the effect of a short-term coculture of early bovine embryos-luteal cells on the in vitro development and embryo quality.