Recent Advances and Future Directions in Sonodynamic Therapy for Cancer Treatment.

Deep-tissue solid cancer treatment has a poor prognosis, resulting in a very low 5-year patient survival rate. The primary challenges facing solid tumor therapies are accessibility, incomplete surgical removal of tumor tissue, the resistance of the hypoxic and heterogeneous tumor microenvironment to chemotherapy and radiation, and suffering caused by off-target toxicities. Here, sonodynamic therapy (SDT) is an evolving therapeutic approach that uses low-intensity ultrasound to target deep-tissue solid tumors.

Ultrasound Therapy, Chemotherapy and Their Combination for Prostate Cancer.

Prostate cancer is the second leading cause of cancer death in men. Its current treatment includes various physical and chemical approaches for the localized and advanced prostate cancer [e.g.

Focused Ultrasound Stimulates ER Localized Mechanosensitive PANNEXIN-1 to Mediate Intracellular Calcium Release in Invasive Cancer Cells.

Focused ultrasound (FUS) is a rapidly developing stimulus technology with the potential to uncover novel mechanosensory dependent cellular processes. Since it is non-invasive, it holds great promise for future therapeutic applications in patients used either alone or as a complement to boost existing treatments. For example, FUS stimulation causes invasive but not non-invasive cancer cell lines to exhibit marked activation of calcium signaling pathways.

Investigation of Ultrasound-Mediated Intracellular Ca Oscillations in HIT-T15 Pancreatic β-Cell Line.

In glucose-stimulated insulin secretion (GSIS) of pancreatic β-cells, the rise of free cytosolic Ca concentration through voltage-gated calcium channels (VGCCs) triggers the exocytosis of insulin-containing granules. Recently, mechanically induced insulin secretion pathways were also reported, which utilize free cytosolic Ca ions as a direct regulator of exocytosis. In this study, we aimed to investigate intracellular Ca responses on the HIT-T15 pancreatic β-cell line upon low-intensity pulsed ultrasound (LIPUS) stimulation and found that ultrasound induces two distinct types of intracellular Ca oscillation, fast-irregular and slow-periodic, from otherwise resting cells.

Low-Intensity Ultrasound Modulates Ca Dynamics in Human Mesenchymal Stem Cells via Connexin 43 Hemichannel.

In recent years, ultrasound has gained attention in new biological applications due to its ability to induce specific biological responses at the cellular level. Although the biophysical mechanisms underlying the interaction between ultrasound and cells are not fully understood, many agree on a pivotal role of Ca signaling through mechanotransduction pathways. Because Ca regulates a vast range of downstream cellular processes, a better understanding of how ultrasound influences Ca signaling could lead to new applications for ultrasound.

Functional Assay of Cancer Cell Invasion Potential Based on Mechanotransduction of Focused Ultrasound.

Cancer cells undergo a number of biophysical changes as they transform from an indolent to an aggressive state. These changes, which include altered mechanical and electrical properties, can reveal important diagnostic information about disease status. Here, we introduce a high-throughput, functional technique for assessing cancer cell invasion potential, which works by probing for the mechanically excitable phenotype exhibited by invasive cancer cells.

Non-coding RNAs derived from an alternatively spliced REST transcript (REST-003) regulate breast cancer invasiveness.

RE1-Silencing Transcription factor (REST) has a well-established role in regulating transcription of genes important for neuronal development. Its role in cancer, though significant, is less well understood. We show that REST downregulation in weakly invasive MCF-7 breast cancer cells converts them to a more invasive phenotype, while REST overexpression in highly invasive MDA-MB-231 cells suppresses invasiveness.

Short-term effects of neoadjuvant chemoradiation therapy on anorectal function in rectal cancer patients: a pilot study.

Background: Neoadjuvant chemoradiation therapy followed by curative surgery has gained acceptance as the therapy of choice in locally advanced rectal cancer. However, deterioration of anorectal function after long-course neoadjuvant chemoradiation therapy combined with surgery for rectal cancer is poorly defined. The aim of this study was to evaluate the physiological and clinical change of anorectal function after neoadjuvant chemoradiation therapy for rectal cancer.

Investigating contactless high frequency ultrasound microbeam stimulation for determination of invasion potential of breast cancer cells.

In this article, we investigate the application of contactless high frequency ultrasound microbeam stimulation (HFUMS) for determining the invasion potential of breast cancer cells. In breast cancer patients, the finding of tumor metastasis significantly worsens the clinical prognosis. Thus, early determination of the potential of a tumor for invasion and metastasis would significantly impact decisions about aggressiveness of cancer treatment.

Imaging the response of the retina to electrical stimulation with genetically encoded calcium indicators.

Epiretinal implants for the blind are designed to stimulate surviving retinal neurons, thus bypassing the diseased photoreceptor layer. Single-unit or multielectrode recordings from isolated animal retina are commonly used to inform the design of these implants. However, such electrical recordings provide limited information about the spatial patterns of retinal activation.

A novel dual-color reporter for identifying insulin-producing beta-cells and classifying heterogeneity of insulinoma cell lines.

Many research studies use immortalized cell lines as surrogates for primary beta- cells. We describe the production and use of a novel "indirect" dual-fluorescent reporter system that leads to mutually exclusive expression of EGFP in insulin-producing (INS(+)) beta-cells or mCherry in non-beta-cells. Our system uses the human insulin promoter to initiate a Cre-mediated shift in reporter color within a single transgene construct and is useful for FACS selection of cells from single cultures for further analysis.

miR-302b maintains "stemness" of human embryonal carcinoma cells by post-transcriptional regulation of Cyclin D2 expression.

Embryonic stem cells (ESCs) and embryonal carcinoma cells (ECCs) possess the remarkable property of self-renewal and differentiation potency. They are model preparations for investigating the underlying mechanisms of "stemness". microRNAs are recently discovered small noncoding RNAs with a broad spectrum of functions, especially in control of development.

Functional and intracellular localization properties of U6 promoter-expressed siRNAs, shRNAs, and chimeric VA1 shRNAs in mammalian cells.

RNA polymerase III (Pol III) expression systems for short hairpin RNAs (U6 shRNAs or chimeric VA1 shRNAs) or individually expressed sense/antisense small interfering RNA (siRNA) strands have been used to trigger RNA interference (RNAi) in mammalian cells. Here we show that individually expressed siRNA expression constructs produce 21-nucleotide siRNAs that strongly accumulate as duplex siRNAs in the nucleus of human cells, exerting sequence-specific silencing activity similar to cytoplasmic siRNAs derived from U6 or VA1-expressed hairpin precursors. In contrast, 29-mer siRNAs separately expressed as sense/antisense strands fail to elicit RNAi activity, despite accumulation of these RNAs in the nucleus.

Cytoplasmic and nuclear retained DMPK mRNAs are targets for RNA interference in myotonic dystrophy cells.

Small interfering RNA (siRNA) duplexes induce the specific cleavage of target RNAs in mammalian cells. Their involvement in down-regulation of gene expression is termed RNA interference (RNAi). It is widely believed that RNAi predominates in the cytoplasm.

Control of HIV-1 replication by RNA interference.

Small interfering RNAs (siRNAs) have been shown to direct sequence-specific inhibition of gene expression in mammalian cells. siRNAs are RNA duplexes of 21-23 nucleotides (nts) with approximately 2nt 3' overhangs that can induce degradation of their homologous target mRNAs without interferon responses in mammalian cells. The degradation of the target occurs at the post-transcriptional level, meaning a post-transcriptional gene silencing (PTGS) mechanism called as RNA interference (RNAi).

Inhibition of HIV-1 infection by lentiviral vectors expressing Pol III-promoted anti-HIV RNAs.

A primary advantage of lentiviral vectors is their ability to pass through the nuclear envelope into the cell nucleus thereby allowing transduction of nondividing cells. Using HIV-based lentiviral vectors, we delivered an anti-CCR5 ribozyme (CCR5RZ), a nucleolar localizing TAR RNA decoy, or Pol III-expressed siRNA genes into cultured and primary cells. The CCR5RZ is driven by the adenoviral VA1 Pol III promoter, while the human U6 snRNA Pol III-transcribed TAR decoy is embedded in a U16 snoRNA (designated U16TAR), and the siRNAs were expressed from the human U6 Pol III promoter.

Inhibition of HIV-1 by lentiviral vector-transduced siRNAs in T lymphocytes differentiated in SCID-hu mice and CD34+ progenitor cell-derived macrophages.

The phenomenon of RNA interference mediated by small interfering RNAs (siRNAs) is a potent gene-silencing mechanism. A number of recent studies demonstrated inhibition of HIV-1 replication in cultured cells using this approach. To make further progress and harness this technology for HIV-1 gene therapy in a stem cell setting, in vivo studies using primary hematopoietic cells are needed.

Small interfering RNAs expressed from a Pol III promoter suppress the EWS/Fli-1 transcript in an Ewing sarcoma cell line.

The EWS/Fli-1 fusion gene encodes an oncogenic fusion protein. The fusion is a product of the translocation t(11;22) (q24;q12), which is detected in 85% of Ewing sarcoma and primitive neuroectodermal tumor cells. Utilizing intracellularly expressed 21- to 23-nucleotide small interfering RNAs (siRNAs) targeting the EWS/Fli-1 fusion transcript in an Ewing sarcoma cell line, we achieved a greater than 80% reduction in the EWS/Fli-1 transcript.

Hammerhead ribozyme-mediated destruction of nuclear foci in myotonic dystrophy myoblasts.

Myotonic dystrophy type 1 (DM1) is caused by an unstable CTG expansion in the 3' untranslated region (3'UTR) of the myotonic dystrophy protein kinase gene (DMPK). Transcripts from this altered gene harbor large CUG expansions that are retained in the nucleus of DM1 cells and form foci. It is believed that the formation of these foci is closely linked to DM1 muscle pathogenesis.

RNA-based anti-HIV-1 gene therapeutic constructs in SCID-hu mouse model.

Effective suppression of HIV-1 replication requires inhibition of critical viral target molecules. Tat and Rev are indispensable regulatory factors for HIV-1 replication, whereas Env mediates virus entry by direct interaction with surface receptor CD4 and coreceptor CCR5 or CXCR4. Anti-HIV-1 tat-rev and env ribozymes and Rev aptamers were previously demonstrated to provide relatively long-term protection against HIV-1 infection in vitro.

Expression of small interfering RNAs targeted against HIV-1 rev transcripts in human cells.

RNA interference (RNAi) is the process of sequence-specific, posttranscriptional gene silencing in animals and plants initiated by double-stranded (ds) RNA that is homologous to the silenced gene. This technology has usually involved injection or transfection of dsRNA in model nonvertebrate organisms. The longer dsRNAs are processed into short (19 25 nucleotides) small interfering RNAs (siRNAs) by a ribonucleotide protein complex that includes an RNAse III related nuclease (Dicer), a helicase family member, and possibly a kinase and an RNA-dependent RNA polymerase (RdRP).