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Sigma-1 Receptor in Cancer Therapy
Research Guide

What is Sigma-1 Receptor in Cancer Therapy?

Sigma-1 receptor in cancer therapy exploits tumor overexpression of sigma-1 receptors for targeted imaging, apoptosis induction, and radiosensitization using selective antagonists and ligands.

Sigma-1 receptors show high expression in diverse human and rodent tumor cell lines, as demonstrated by Vilner et al. (1995) across 13 lines using [3H](+)-pentazocine labeling (488 citations). Ligands induce cytotoxic effects like morphological changes and viability loss in glioma cells (Vil'ner et al., 1995; 168 citations). Therapeutic potential includes sigma receptor ligands for cancer diagnosis and therapy (van Waarde et al., 2014; 156 citations).

Curated Papers

Key Challenges

Why It Matters

Sigma-1 overexpression in tumors enables antagonist-induced apoptosis, addressing chemoresistance in aggressive cancers (Vilner et al., 1995; Vil'ner et al., 1995). Selective ligands support PET imaging and targeted chemotherapy delivery (van Waarde et al., 2014). Sigma-1 modulation degrades PD-L1 via autophagy, enhancing immunotherapy (Maher et al., 2017). These strategies improve outcomes in glioma and other tumors via receptor-mediated cytotoxicity (Cobos et al., 2008).

Key Research Challenges

Sigma-1 vs Sigma-2 Selectivity

Distinguishing sigma-1 from sigma-2 receptors is critical due to their co-expression in tumors (Vilner et al., 1995). Lack of selective ligands complicates targeted therapy (Cobos et al., 2008). Recent identification of sigma-2 as TMEM97 highlights need for sigma-1-specific tools (Alon et al., 2017).

Overcoming Tumor Chemoresistance

Sigma-1 antagonists induce apoptosis but face resistance in advanced tumors (Vil'ner et al., 1995). Combining with radiosensitization requires optimized dosing (van Waarde et al., 2014). Understanding sigma-1 signaling in cancer homeostasis remains incomplete (Maher et al., 2017).

Ligand Development for Imaging

Developing high-affinity sigma-1 ligands for PET imaging demands specificity amid off-target effects (van Waarde et al., 2014). Tumor heterogeneity affects receptor density quantification (Vilner et al., 1995). Clinical translation needs validated pharmacokinetics (Cobos et al., 2008).

Essential Papers

Sigma-1 and sigma-2 receptors are expressed in a wide variety of human and rodent tumor cell lines.

Bertold J. Vilner, Christy S. John, W D Bowen · 1995 · PubMed · 488 citations

Thirteen tumor-derived cell lines of human and nonhuman origin and from various tissues were examined for the presence and density of sigma-1 and sigma-2 receptors. Sigma-1 receptors of a crude mem...

Pharmacology and Therapeutic Potential of Sigma1 Receptor Ligands

Enrique J. Cobos, José Manuel Entrena, Francisco R. Nieto et al. · 2008 · Current Neuropharmacology · 367 citations

Sigma (sigma) receptors, initially described as a subtype of opioid receptors, are now considered unique receptors. Pharmacological studies have distinguished two types of sigma receptors, termed s...

Alzheimer's Therapeutics Targeting Amyloid Beta 1–42 Oligomers II: Sigma-2/PGRMC1 Receptors Mediate Abeta 42 Oligomer Binding and Synaptotoxicity

Nicholas J. Izzo, Jinbin Xu, Chenbo Zeng et al. · 2014 · PLoS ONE · 291 citations

Amyloid beta (Abeta) 1–42 oligomers accumulate in brains of patients with Mild Cognitive Impairment (MCI) and disrupt synaptic plasticity processes that underlie memory formation. Synaptic binding ...

Identification of the gene that codes for the σ<sub>2</sub>receptor

Assaf Alon, Hayden R. Schmidt, Michael D. Wood et al. · 2017 · Proceedings of the National Academy of Sciences · 262 citations

Significance Of the many receptors that were pharmacologically described during the 20th century, almost all were cloned by the end of the 1990s. A key exception is the σ 2 receptor, a potential th...

Association between antidepressant use and reduced risk of intubation or death in hospitalized patients with COVID-19: results from an observational study

Nicolas Hoertel, Marina Sánchez‐Rico, Raphaël Vernet et al. · 2021 · Molecular Psychiatry · 249 citations

Neuronal Sigma-1 Receptors: Signaling Functions and Protective Roles in Neurodegenerative Diseases

Daniel A. Ryskamp, Svetlana A. Korban, Vladimir Zhemkov et al. · 2019 · Frontiers in Neuroscience · 195 citations

Sigma-1 receptor (S1R) is a multi-functional, ligand-operated protein situated in endoplasmic reticulum (ER) membranes and changes in its function and/or expression have been associated with variou...

Cytotoxic effects of sigma ligands: sigma receptor-mediated alterations in cellular morphology and viability

B. Ya. Vil'ner, BR de Costa, WD Bowen · 1995 · Journal of Neuroscience · 168 citations

The morphological effects of several neuroleptics as well as other novel and prototypic sigma ligands were examined by addition to cultures of C6 glioma cells. Sigma ligands caused loss of processe...

Reading Guide

Foundational Papers

Start with Vilner et al. (1995; 488 citations) for tumor expression evidence and Vil'ner et al. (1995; 168 citations) for cytotoxicity mechanisms, as they establish core observations in 13 cell lines.

Recent Advances

Study Maher et al. (2017; 155 citations) for PD-L1 autophagy and Alon et al. (2017; 262 citations) for sigma-2 identity impacting sigma-1 specificity.

Core Methods

Core techniques include [3H](+)-pentazocine radiolabeling for sigma-1 density (Vilner et al., 1995), morphological assays for cytotoxicity (Vil'ner et al., 1995), and ligand modulation for autophagy (Maher et al., 2017).

How PapersFlow Helps You Research Sigma-1 Receptor in Cancer Therapy

Discover & Search

Research Agent uses searchPapers and exaSearch to find sigma-1 cancer papers like Vilner et al. (1995), then citationGraph reveals 488 citing works on tumor expression, and findSimilarPapers uncovers related apoptosis studies.

Analyze & Verify

Analysis Agent applies readPaperContent to extract binding affinities from Vilner et al. (1995), verifies claims with CoVe against Cobos et al. (2008), and runs PythonAnalysis to plot receptor densities across 13 tumor lines with statistical tests; GRADE scores evidence strength for therapeutic claims.

Synthesize & Write

Synthesis Agent detects gaps in sigma-1 selectivity via contradiction flagging across Vilner (1995) and Alon (2017), while Writing Agent uses latexEditText, latexSyncCitations for Vilner et al., and latexCompile to generate therapy review manuscripts with exportMermaid for receptor signaling diagrams.

Use Cases

"Analyze sigma-1 receptor densities in tumor cell lines from Vilner 1995 with statistics"

Research Agent → searchPapers('Vilner sigma tumor') → Analysis Agent → readPaperContent + runPythonAnalysis(pandas plot of densities, t-test p-values) → researcher gets CSV of densities and matplotlib density plot.

"Write LaTeX review on sigma-1 ligands in cancer therapy citing van Waarde 2014"

Synthesis Agent → gap detection → Writing Agent → latexEditText(structure review) → latexSyncCitations(van Waarde) → latexCompile → researcher gets compiled PDF with figures.

"Find code for sigma-1 ligand binding simulations"

Research Agent → paperExtractUrls → Code Discovery → paperFindGithubRepo → githubRepoInspect → researcher gets annotated GitHub repos with docking scripts.

Automated Workflows

Deep Research workflow scans 50+ sigma-1 papers via citationGraph from Vilner (1995), producing structured reports on tumor expression trends. DeepScan applies 7-step CoVe to verify apoptosis claims in Vil'ner (1995) with GRADE checkpoints. Theorizer generates hypotheses on sigma-1/PD-L1 links from Maher (2017).

Try Doxa for Sigma-1 Receptor in Cancer Therapy Research

Frequently Asked Questions

What defines Sigma-1 receptor in cancer therapy?

Sigma-1 receptor in cancer therapy uses tumor overexpression for ligand-induced apoptosis and imaging (Vilner et al., 1995).

What methods target Sigma-1 in tumors?

[3H](+)-pentazocine labels sigma-1 in membranes; antagonists alter glioma morphology and viability (Vilner et al., 1995; Vil'ner et al., 1995).

What are key papers on Sigma-1 in cancer?

Vilner et al. (1995; 488 citations) shows expression in 13 tumor lines; van Waarde et al. (2014; 156 citations) covers diagnostic ligands; Maher et al. (2017; 155 citations) links to PD-L1 degradation.