Short hairpin RNA screen indicates that Klotho beta/FGF19 protein overcomes stasis in human colonic epithelial cells.

Normal human colonic epithelial cells (HCECs) are not immortalized by telomerase alone but also require CDK4. Some human cell types growth-arrest due to stress- or aberrant signaling-induced senescence (stasis). Stasis represents the consequences of growth conditions culture that are inadequate to maintain long-term proliferation.

Role of telomeres and telomerase in cancer.

There is mounting evidence for the existence of an important relationship between telomeres and telomerase and cellular aging and cancer. Normal human cells progressively lose telomeres with each cell division until a few short telomeres become uncapped leading to a growth arrest known as replicative aging. In the absence of genomic alterations these cells do not die but remain quiescent producing a different constellation of proteins compared to young quiescent cells.

Development of methods for quantitative comparison of pooled shRNAs by mass sequencing.

Pooled short-hairpin RNA (shRNA) library screening is a powerful tool for identifying a set of genes in biological pathways that require stable expression to produce a desired phenotype. Massive parallel sequencing of half-hairpins has proven highly variable and has not given satisfactory results concerning the relative abundance of different shRNAs before and after selection. Here, the authors describe a method for quantitative comparison of half-hairpins from pooled shRNAs in the mir30-based pGIPZ vector that is analyzed by massive parallel sequencing.

From mice and men to earth and space: joint NASA-NCI workshop on lung cancer risk resulting from space and terrestrial radiation.

On June 27-28, 2011, scientists from the National Cancer Institute (NCI), NASA, and academia met in Bethesda to discuss major lung cancer issues confronting each organization. For NASA, available data suggest that lung cancer is the largest potential cancer risk from space travel for both men and women and quantitative risk assessment information for mission planning is needed. In space, the radiation risk is from high energy and charge (HZE) nuclei (such as Fe) and high-energy protons from solar flares and not from gamma radiation.

Casualties.

Privation and disease have mainly killed soldiers until very recently. Now that enemy action predominates, faster and better control of bleeding and infection before and during evacuation spares ever more lives today. This essay focuses on psychological war wounds, placing them in the context of military casualties.

Impact of perioperative RSV or influenza infection on length of stay and risk of unplanned ICU admission in children: a case-control study.

Background: Children with viral respiratory infections who undergo general anesthesia are at increased risk of respiratory complications. We investigated the impact of RSV and influenza infection on perioperative outcomes in children undergoing general anesthesia.

Methods: We performed a retrospective case-control study.

Is telomerase a viable target in cancer?

The ideal cancer treatment would specifically target cancer cells yet have minimal or no adverse effects on normal somatic cells. Telomerase, the ribonucleoprotein reverse transcriptase that maintains the ends of human chromosome, is an attractive cancer therapeutic target for exactly this reason [1]. Telomerase is expressed in more than 85% of cancer cells, making it a nearly universal cancer marker, while the majority of normal somatic cells are telomerase negative.

Establishment of clonal myogenic cell lines from severely affected dystrophic muscles - CDK4 maintains the myogenic population.

Background: A hallmark of muscular dystrophies is the replacement of muscle by connective tissue. Muscle biopsies from patients severely affected with facioscapulohumeral muscular dystrophy (FSHD) may contain few myogenic cells. Because the chromosomal contraction at 4q35 linked to FSHD is thought to cause a defect within myogenic cells, it is important to study this particular cell type, rather than the fibroblasts and adipocytes of the endomysial fibrosis, to understand the mechanism leading to myopathy.

Multipotent capacity of immortalized human bronchial epithelial cells.

While the adult murine lung utilizes multiple compartmentally restricted progenitor cells during homeostasis and repair, much less is known about the progenitor cells from the human lung. Translating the murine stem cell model to humans is hindered by anatomical differences between species. Here we show that human bronchial epithelial cells (HBECs) display characteristics of multipotent stem cells of the lung.

Pregnane X receptor activation induces FGF19-dependent tumor aggressiveness in humans and mice.

The nuclear receptor pregnane X receptor (PXR) is activated by a range of xenochemicals, including chemotherapeutic drugs, and has been suggested to play a role in the development of tumor cell resistance to anticancer drugs. PXR also has been implicated as a regulator of the growth and apoptosis of colon tumors. Here, we have used a xenograft model of colon cancer to define a molecular mechanism that might underlie PXR-driven colon tumor growth and malignancy.

Functional parsing of driver mutations in the colorectal cancer genome reveals numerous suppressors of anchorage-independent growth.

Landmark cancer genome resequencing efforts are leading to the identification of mutated genes in many types of cancer. The extreme diversity of mutations being detected presents significant challenges to subdivide causal from coincidental mutations to elucidate how disrupted regulatory networks drive cancer processes. Given that a common early perturbation in solid tumor initiation is bypass of matrix-dependent proliferation restraints, we sought to functionally interrogate colorectal cancer candidate genes (CAN-genes) to identify driver tumor suppressors.

Comparative biology of mammalian telomeres: hypotheses on ancestral states and the roles of telomeres in longevity determination.

Progressive telomere shortening from cell division (replicative aging) provides a barrier for human tumor progression. This program is not conserved in laboratory mice, which have longer telomeres and constitutive telomerase. Wild species that do/do not use replicative aging have been reported, but the evolution of different phenotypes and a conceptual framework for understanding their uses of telomeres is lacking.

Characterization of aneuploid populations with trisomy 7 and 20 derived from diploid human colonic epithelial cells.

Chromosomal instability leading to aneuploidy occurs in most sporadic colorectal cancers (CRCs) and is believed to be an early driving force in disease progression. Despite this observation, the cellular advantages conferred by these cytogenetic alterations are poorly understood. Here, we provide evidence that serum-free passage of originally diploid, immortalized human colonic epithelial cells (HCECs) gave rise to the acquisition of trisomy 7 (+7), an aneuploidy detected in more than 40% of colorectal adenomas.

Projective identification simplified: recruiting your shadow.

One of the many gifts of Anne Alonso was her ability to simplify the practice of psychotherapy for her students so that it was accessible without being “dumbed down.” In that spirit, I hope to simplify the murky concept of projective identification so it is readily useable for therapists, especially, in this article, for group therapists. I describe how I teach the concept, which includes the use of visual aids (cartoons, TV and movie clips, and diagrams), and suggest that we replace it with a construct which is less murky and, as a result, more accessible.

Telomere terminal G/C strand synthesis: measuring telomerase action and C-rich fill-in.

Telomerase is present in most human cancers, and proliferative stem cells including germline cells. Telomerase plays an essential role in tumorigenesis by maintaining/elongating telomeric DNA, and thus preventing the telomere shortening that results in replicative senescence. Understanding telomerase action in vivo has important implication for both cancer and aging, but there are not robust methods for monitoring telomerase action.

Telomere G-overhang length measurement method 1: the DSN method.

Telomeres terminate in 3' single-stranded G-overhangs that function in telomere end protection and telomerase action. An accurate measurement of overhang length is challenging due to the presence of many kilobases of double-stranded telomere DNA. Here, a simple method is described that utilizes duplex-specific nuclease (DSN) to digest all genomic DNA including telomeres, leaving the single-stranded overhangs intact.

Irreparable complex DNA double-strand breaks induce chromosome breakage in organotypic three-dimensional human lung epithelial cell culture.

DNA damage and consequent mutations initiate the multistep carcinogenic process. Differentiated cells have a reduced capacity to repair DNA lesions, but the biological impact of unrepaired DNA lesions in differentiated lung epithelial cells is unclear. Here, we used a novel organotypic human lung three-dimensional (3D) model to investigate the biological significance of unrepaired DNA lesions in differentiated lung epithelial cells.

Purkinje cell-specific males absent on the first (mMof) gene deletion results in an ataxia-telangiectasia-like neurological phenotype and backward walking in mice.

The brains of ataxia telangiectasia (AT) patients display an aberrant loss of Purkinje cells (PCs) that is postulated to contribute to the observed deficits in motor coordination as well as in learning and cognitive function. AT patients have mutations in the ataxia telangiectasia mutated (ATM) gene [Savitsky et al. (1995) Science 268:1749-1753].

Aldehyde dehydrogenase activity selects for lung adenocarcinoma stem cells dependent on notch signaling.

Aldehyde dehydrogenase (ALDH) is a candidate marker for lung cancer cells with stem cell-like properties. Immunohistochemical staining of a large panel of primary non-small cell lung cancer (NSCLC) samples for ALDH1A1, ALDH3A1, and CD133 revealed a significant correlation between ALDH1A1 (but not ALDH3A1 or CD133) expression and poor prognosis in patients including those with stage I and N0 disease. Flow cytometric analysis of a panel of lung cancer cell lines and patient tumors revealed that most NSCLCs contain a subpopulation of cells with elevated ALDH activity, and that this activity is associated with ALDH1A1 expression.

Alternative splicing of caspase 9 is modulated by the phosphoinositide 3-kinase/Akt pathway via phosphorylation of SRp30a.

Increasing evidence points to the functional importance of alternative splice variations in cancer pathophysiology. Two splice variants are derived from the CASP9 gene via the inclusion (Casp9a) or exclusion (Casp9b) of a four-exon cassette. Here we show that alternative splicing of Casp9 is dysregulated in non-small cell lung cancers (NSCLC) regardless of their pathologic classification.