Integrative analysis reveals therapeutic potential of pyrvinium pamoate in Merkel cell carcinoma.

Merkel Cell Carcinoma (MCC) is a highly aggressive neuroendocrine cutaneous malignancy arising from either ultraviolet-induced mutagenesis or Merkel cell polyomavirus (MCPyV) integration. It is the only known neuroendocrine tumor (NET) with a virus etiology. Despite extensive research, our understanding of the molecular mechanisms driving the transition from normal cells to MCC remains limited. To address this knowledge gap, we assessed the impact of inducible MCPyV T antigens into normal human fibroblasts by performing RNA sequencing. Our findings suggested that the WNT signaling pathway plays a critical role in the development of MCC. To test this model, we bioinformatically evaluated various perturbagens for their ability to reverse the MCC gene expression signature and identified pyrvinium pamoate, an FDA-approved anthelminthic drug known for its anti-tumor potential in multiple cancers. Leveraging transcriptomic, network, and molecular analyses, we found that pyrvinium effectively targets multiple MCC vulnerabilities. Specifically, pyrvinium not only reverses the neuroendocrine features of MCC by modulating canonical and non-canonical WNT signaling pathways but also inhibits cancer cell growth by activating the p53-mediated apoptosis pathway, disrupting mitochondrial function, and inducing endoplasmic reticulum (ER) stress. Pyrvinium also effectively inhibits tumor growth in an MCC mouse xenograft model. These findings offer new avenues for the development of therapeutic strategies for neuroendocrine cancer and highlight the utility of pyrvinium as a potential treatment for MCC.

Structural and functional integration of human forebrain organoids with the injured adult rat visual system.

Brain organoids created from human pluripotent stem cells represent a promising approach for brain repair. They acquire many structural features of the brain and raise the possibility of patient-matched repair. Whether these entities can integrate with host brain networks in the context of the injured adult mammalian brain is not well established. Here, we provide structural and functional evidence that human brain organoids successfully integrate with the adult rat visual system after transplantation into large injury cavities in the visual cortex. Virus-based trans-synaptic tracing reveals a polysynaptic pathway between organoid neurons and the host retina and reciprocal connectivity between the graft and other regions of the visual system. Visual stimulation of host animals elicits responses in organoid neurons, including orientation selectivity. These results demonstrate the ability of human brain organoids to adopt sophisticated function after insertion into large injury cavities, suggesting a translational strategy to restore function after cortical damage.

PIM Kinase Inhibitors Block the Growth of Primary T-cell Acute Lymphoblastic Leukemia: Resistance Pathways Identified by Network Modeling Analysis.

Despite significant progress in understanding the genetic landscape of T-cell acute lymphoblastic leukemia (T-ALL), the discovery of novel therapeutic targets has been difficult. Our results demonstrate that the levels of PIM1 protein kinase is elevated in early T-cell precursor ALL (ETP-ALL) but not in mature T-ALL primary samples. Small-molecule PIM inhibitor (PIMi) treatment decreases leukemia burden in ETP-ALL. However, treatment of animals carrying ETP-ALL with PIMi was not curative. To model other pathways that could be targeted to complement PIMi activity, HSB-2 cells, previously characterized as a PIMi-sensitive T-ALL cell line, were grown in increasing doses of PIMi. Gene set enrichment analysis of RNA sequencing data and functional enrichment of network modules demonstrated that the HOXA9, mTOR, MYC, NFκB, and PI3K-AKT pathways were activated in HSB-2 cells after long-term PIM inhibition. Reverse phase protein array-based pathway activation mapping demonstrated alterations in the mTOR, PI3K-AKT, and NFκB pathways, as well. PIMi-tolerant HSB-2 cells contained phosphorylated RelA-S536 consistent with activation of the NFκB pathway. The combination of NFκB and PIMis markedly reduced the proliferation in PIMi-resistant leukemic cells showing that this pathway plays an important role in driving the growth of T-ALL. Together these results demonstrate key pathways that are activated when HSB-2 cell line develop resistance to PIMi and suggest pathways that can be rationally targeted in combination with PIM kinases to inhibit T-ALL growth.

Generating Ensembles of Gene Regulatory Networks to Assess Robustness of Disease Modules.

The use of biological networks such as protein-protein interaction and transcriptional regulatory networks is becoming an integral part of genomics research. However, these networks are not static, and during phenotypic transitions like disease onset, they can acquire new "communities" (or highly interacting groups) of genes that carry out cellular processes. Disease communities can be detected by maximizing a modularity-based score, but since biological systems and network inference algorithms are inherently noisy, it remains a challenge to determine whether these changes represent real cellular responses or whether they appeared by random chance. Here, we introduce Constrained Random Alteration of Network Edges (CRANE), a method for randomizing networks with fixed node strengths. CRANE can be used to generate a null distribution of gene regulatory networks that can in turn be used to rank the most significant changes in candidate disease communities. Compared to other approaches, such as consensus clustering or commonly used generative models, CRANE emulates biologically realistic networks and recovers simulated disease modules with higher accuracy. When applied to breast and ovarian cancer networks, CRANE improves the identification of cancer-relevant GO terms while reducing the signal from non-specific housekeeping processes.

Sacral nerve stimulation for fecal incontinence: long-term outcomes.

BACKGROUND: Numerous studies advocate the short-term benefits of sacral nerve stimulation for fecal incontinence, but there has been a paucity of studies on longer-term outcomes. OBJECTIVE: The objective of this study was to report the long-term outcome of sacral nerve stimulation performed for fecal incontinence at a single institution. PATIENTS AND DESIGN: Between January 2004 and May 2007, 53 patients underwent definitive sacral nerve stimulation for fecal incontinence at our institution. Prospectively recorded baseline information, including Wexner incontinence scores and standard short-form (SF-12) health survey scores, were compared with scores at follow-up. RESULTS: Forty-one patients were available for long-term follow-up with a mean duration of 51 months. The median Wexner score decreased from a baseline of 11.5 (range, 3.0-18.0) to 8.0 (range, 0.0-18.0) at follow-up. The mean difference in Wexner score was 2.7 (P < .001). There was no statistically significant change in SF-12 physical scores, but a small but highly significant change occurred in SF-12 mental scores. The median SF-12 mental domain score was 49.5 (range, 15.0-62.1) at baseline, and 57.0 (range, 20.0-64.0) at follow-up, with a mean difference of 4.5 (P = .006). Subgroup analysis performed comparing patients with or without prior intersphincteric silicon biomaterial implants demonstrated a mean difference in Wexner score of -3.5 (no implant) vs 0.0 (previous implant), with P < .09 (not statistically significant). CONCLUSIONS: Sacral nerve stimulation results in a statistically significant improvement in fecal incontinence scores in the long term.

"Gunsight" skin incision and closure technique for stoma reversal.

BACKGROUND: Several techniques have been described in the literature for skin closure following stoma reversal. We describe the "gunsight skin closure" technique and highlight its potential advantages. METHOD: Four triangles of skin are excised to enlarge the skin incision. This increases exposure for mobilization of the bowel. The resulting skin wound is approximated with a pursestring suture to give a small, neat scar that allows some central drainage. The final wound resembles a gunsight. CONCLUSION: This method of skin closure allows increased surgical exposure, facilitates creation of a subsequent stoma at the same site, simplifies wound care, and gives a neat cosmetic result.