Research Methods in Molecular Biology Study
48 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What method was used to quantify RNA in the study?

  • Spectrophotometric analysis (correct)
  • Fluorometric analysis
  • Electrophoresis
  • Real-time quantitative PCR

Which protein staining method confirmed protein loading in Western blot?

  • Silver staining
  • Revert 700 Total Protein Stain (correct)
  • Ponceau S staining
  • Coomassie Brilliant Blue

Which of the following mRNAs were detected using qPCR in the study?

  • b-Actin, ENPP2
  • CD63, CD9, CD81
  • DNase, TURBO
  • Autotaxin, LPAR1, LPAR3, LPAR5 (correct)

What type of animals were the samples taken from in the study?

<p>Tumor-bearing mice (A)</p> Signup and view all the answers

What was the purpose of using TURBO DNase in the RNA isolation process?

<p>To eliminate DNA contamination (A)</p> Signup and view all the answers

Which kit was used for cDNA synthesis in the study?

<p>ProtoScript II First Strand cDNA Synthesis Kit (D)</p> Signup and view all the answers

How were the Western blot membranes visualized?

<p>IRDye 800CW goat anti-rabbit secondary antibody (B)</p> Signup and view all the answers

Which software was used for the analysis of total protein and immunoreactivity?

<p>ImageJ (D)</p> Signup and view all the answers

What role did J.J. play in the research described in the content?

<p>Performed RT-qPCR and western blot studies (A)</p> Signup and view all the answers

Which method was NOT mentioned as performed by the researchers?

<p>Nuclear magnetic resonance (C)</p> Signup and view all the answers

Who coordinated the study and contributed to the electrophysiology experiments?

<p>D.A.S. (B)</p> Signup and view all the answers

What specific type of cells did A.F. contribute to regarding LPA treatment?

<p>Fibrosarcoma cells in vitro (B)</p> Signup and view all the answers

Which of the following was NOT a focus of the experiments as described?

<p>Gene editing techniques (D)</p> Signup and view all the answers

What was the primary outcome related to the role of lysophosphatidic acid receptor signaling?

<p>Requirement for neuropathic pain (A)</p> Signup and view all the answers

Which team member's contribution involved mass spectrometric assay and data analysis?

<p>W.Z. (A)</p> Signup and view all the answers

Which process did V.S.S. participate in regarding the effects of lysophosphatidic acid?

<p>Chemotaxis (A)</p> Signup and view all the answers

What type of neurons were isolated in the study?

<p>Dorsal root ganglion neurons (B)</p> Signup and view all the answers

After how many days did hypersensitivity develop post-implantation of fibrosarcoma?

<p>10 days (C)</p> Signup and view all the answers

Which medium was used for maintaining the primary cultures?

<p>Ham F12/DMEM medium (D)</p> Signup and view all the answers

What specific indicator was used to measure free intracellular calcium levels?

<p>Indo-1 (A)</p> Signup and view all the answers

Which fibroblasts did NOT produce hypersensitivity in naive mice?

<p>NCTC 929 fibroblasts (B)</p> Signup and view all the answers

What effect did tumor-bearing mice have on serum levels of LPA?

<p>Elevation of LPA levels (C)</p> Signup and view all the answers

Which species of LPA were found to be elevated in tumor-bearing mice?

<p>18:1-LPA, 18:2-LPA, and 20:4-LPA (C)</p> Signup and view all the answers

How were cells maintained before use in the experiments?

<p>In a humidified atmosphere of 5% CO2 at 37˚C (D)</p> Signup and view all the answers

What effect was confirmed by counting cells in the study mentioned?

<p>The promitory effect of 18:1-LPA on fibrosarcoma cells. (B)</p> Signup and view all the answers

Which component was adjusted to achieve the desired osmolarity in the HEPES-Hank’s solution?

<p>Sucrose concentration. (A)</p> Signup and view all the answers

What was the outcome of intraplantar injection of H2L5765834 at a higher dose?

<p>It reduced mechanical hypersensitivity. (C)</p> Signup and view all the answers

What type of cells were incubated with indo-1 in the experiment?

<p>Neurons. (A)</p> Signup and view all the answers

Which receptors are expressed by neurons as mentioned in the content?

<p>LPARs 1, 3, 5. (A)</p> Signup and view all the answers

What was the method used to create a baseline for each neuron during the experiment?

<p>Superfusion with HEPES buffer. (C)</p> Signup and view all the answers

What was the temperature maintained during the superfusion process?

<p>25 ± 1˚C. (D)</p> Signup and view all the answers

What was the concentration of KCl used in the stimulation of the cells?

<p>25 mM. (D)</p> Signup and view all the answers

What role does ATX play in the context of target cells?

<p>ATX generates LPA in the vicinity of its receptors. (C)</p> Signup and view all the answers

What is a significant finding regarding cancer exosomes compared to nonmalignant fibroblasts?

<p>Cancer exosomes contain more ATX per unit of exosome mass. (D)</p> Signup and view all the answers

What important function do exosome-bound ATX serve in relation to LPA?

<p>They carry LPA to distally located LPAR. (C)</p> Signup and view all the answers

Which cells may have a contribution to nociceptor sensitization according to the findings?

<p>Immune and glial cells may contribute. (B)</p> Signup and view all the answers

Which method was used for the analysis of exosomes in the study?

<p>Electron microscopy. (D)</p> Signup and view all the answers

What is the primary focus of the study discussed in the article?

<p>The interaction between cancer cells and sensory neurons (D)</p> Signup and view all the answers

What aspect of nociceptor sensitization has been demonstrated in vitro?

<p>Effects attributed to cancer exosomes. (B)</p> Signup and view all the answers

Which compound was found to decrease hyperalgesia in mice with bone cancer pain?

<p>Resolvin D1 and E1 (B)</p> Signup and view all the answers

How are exosome-derived ATX levels related to cancer cell activity?

<p>Higher ATX levels correlate with cancer cell exosome secretion. (A)</p> Signup and view all the answers

What mechanism does increasing 2-arachidonoyl glycerol signaling affect in bone cancer pain models?

<p>It decreases mechanical hyperalgesia. (A)</p> Signup and view all the answers

What type of funding supported the research discussed?

<p>NIH grants. (A)</p> Signup and view all the answers

Which of the following is specifically associated with the signaling mechanisms in metastatic oral cancers?

<p>Exosomal mediators (D)</p> Signup and view all the answers

Which type of cells are involved in the chemical interactions contributing to cancer pain?

<p>Fibrosarcoma cancer cells (B)</p> Signup and view all the answers

What role does anandamide signaling play in the context of cutaneous pain?

<p>It contributes to maintaining cutaneous pain. (C)</p> Signup and view all the answers

Which signaling molecule's administration was studied for its effects on hyperalgesia in bone cancer pain?

<p>Resolvin D (A)</p> Signup and view all the answers

Which of the following signaling pathways was highlighted as a potential target for alleviating cancer pain?

<p>Endocannabinoid signaling (C)</p> Signup and view all the answers

Flashcards

Real-time Quantitative PCR (RT-qPCR)

A method used to measure the amount of specific mRNA molecules present in a sample. It involves reverse transcription (converting RNA to DNA), followed by PCR amplification using primers specific to the target mRNA.

b-Actin

A common housekeeping gene used as a reference in RT-qPCR analysis. It's used to normalize the expression levels of target genes, ensuring accurate comparisons.

Western blot analysis

A technique for analyzing proteins. It involves separating proteins based on their size using electrophoresis, then detecting specific proteins with antibodies.

Antibody

A type of antibody used to detect specific target proteins in a Western blot. It binds to the protein of interest, allowing for visualization.

Signup and view all the flashcards

Exosomes

Tiny vesicles produced by cells. They contain various proteins, lipids, and nucleic acids, potentially communicating signals between cells.

Signup and view all the flashcards

Autotaxin (ATX)

A protein that plays a role in cell signaling. It is involved in regulating inflammation, cell migration, and other processes.

Signup and view all the flashcards

Lysophosphatidic acid receptor (LPAR)

A type of receptor protein that binds to signaling molecules called lysophosphatidic acid (LPA). They are found on the surface of cells and are involved in various cellular processes.

Signup and view all the flashcards

Sonication

A process that involves breaking down a substance into smaller particles. This is often used to prepare samples for analysis.

Signup and view all the flashcards

Nociceptive Neuron

A type of neuron that is sensitive to painful stimuli.

Signup and view all the flashcards

Lysophosphatidic Acid (LPA)

A type of signaling lipid that is involved in a variety of cellular processes, including inflammation and cell growth.

Signup and view all the flashcards

H2L5765834

A type of LPAR antagonist that blocks the action of LPA.

Signup and view all the flashcards

Calcium Imaging

A type of experiment that involves measuring the amount of calcium entering a cell. This is used to study how cells respond to stimuli.

Signup and view all the flashcards

Antimetastatic

The process of reducing the ability of a cell to grow and multiply.

Signup and view all the flashcards

Schwann Cell

A type of cell in the body that is responsible for supporting and nourishing nerve cells (neurons).

Signup and view all the flashcards

In Vitro

A method used to investigate the effects of drugs or other substances on cells.

Signup and view all the flashcards

Dorsal Root Ganglion (DRG) Neuron

A type of neuron found in the dorsal root ganglion, a collection of nerve cell bodies located in the spinal cord. These neurons are responsible for transmitting sensory information from the periphery to the central nervous system.

Signup and view all the flashcards

Isolation of Adult Murine DRG Neurons

A process involving the separation and isolation of individual DRG neurons from a larger tissue sample. This method typically involves enzymatic digestion and mechanical disruption of the tissue.

Signup and view all the flashcards

Primary Culture of Dissociated DRG

A type of laboratory-grown cells that resemble the original source tissue. In this case, they are derived from the mouse dorsal root ganglion (DRG).

Signup and view all the flashcards

Free Intracellular Calcium ([Ca2+]i)

A measure of the concentration of free calcium ions (Ca2+) inside a cell. This is an indicator of cell activity and signaling.

Signup and view all the flashcards

Dual-Emission Microfluorimeter

A technique used to measure [Ca2+]i in individual cells. It involves using a fluorescent indicator (like indo-1) that changes its fluorescence intensity depending on the concentration of calcium ions.

Signup and view all the flashcards

Mouse NCTC clone 2472 Fibrosarcoma

A type of cancer cell line derived from mouse fibroblasts. These cells can form tumors and are used in experiments to study the effects of cancer on the nervous system.

Signup and view all the flashcards

Mouse Clone NCTC 929 Fibroblasts

A type of non-malignant fibroblast cell line derived from mouse cells. These cells are used as a control group in experiments to compare with cancerous cells.

Signup and view all the flashcards

ATX localization

A protein that increases the activity of ATX at specific locations in the cell, leading to increased production of LPA.

Signup and view all the flashcards

ATX-integrin interaction

The process by which ATX binds to integrins on the surface of target cells, facilitating the release and subsequent re-generation of LPA.

Signup and view all the flashcards

Cancer cell exosome-mediated LPA production

A process by which cancer cells produce and release significant amounts of LPA through ATX-containing exosomes.

Signup and view all the flashcards

Cancer exosomes and ATX

A process where cancer cells secrete more exosomes than non-cancerous cells, and these exosomes contain higher levels of ATX, contributing to LPA-mediated hypersensitivity.

Signup and view all the flashcards

Study Notes

Exosome-Associated Lysophosphatidic Acid Signaling in Cancer Pain

  • Pain associated with bone cancer is poorly managed, and chemotherapy often exacerbates pain.
  • Dual-acting drugs that both treat cancer and reduce pain are ideal.
  • Bone cancer pain mechanisms involve interactions between cancer cells and pain-signaling neurons.
  • Fibrosarcoma cells express high levels of autotaxin (ATX), producing lysophosphatidic acid (LPA).
  • LPA increases fibrosarcoma cell proliferation in vitro.
  • LPA activates LPA receptors (LPARs) on pain-signaling neurons and cells in the dorsal root ganglia (DRG).
  • LPA levels are elevated in the serum of mice with implanted tumors.
  • Blocking ATX or LPARs reduces tumor-induced hypersensitivity in mice.
  • Cancer cell-derived exosomes contribute to hypersensitivity, and ATX is found on exosomes.
  • Injecting cancer exosomes into mice causes hypersensitivity, sensitizing pain-signaling C-fibers.
  • Inhibiting ATX or blocking LPARs reduces cancer exosome-induced hypersensitivity.
  • Cancer exosomes directly sensitize DRG neurons through ATX-LPA-LPAR signaling.
  • Targeting the cancer exosome-mediated pathway could treat tumor growth and pain in bone cancer patients.

Methods

  • Animals: Adult male and female C3H/He mice (25-30g) were used, with procedures approved by the Institutional Animal Care and Use Committee.
  • Drugs: Lysophosphatidic acid (LPA) species and their deuterated standards, LPA receptor antagonist (H2L5765834), and autotaxin (ATX) inhibitor (BI-2545) were used.
  • Blood analysis: Serum LPA levels were measured using ELISA and UPLC-MS/MS.
  • Behavioral analysis: Mechanical and heat hypersensitivity were measured using a von Frey monofilament and a Peltier device, respectively.
  • Quantitative PCR (qPCR): mRNA levels of ATX, LPAR1, LPAR3, and LPAR5 were quantified in DRG and paw skin.
  • Exosome isolation: Exosomes were isolated from culture media conditioned by either cancer or fibroblast cells using centrifugation.
  • Nanoparticle tracking analysis (NTA): Particle size distribution and concentration of exosomes were measured.
  • Western blot analysis: Protein expression of CD63, CD9, CD81, ATX, LPAR1, LPAR3, and LPAR5 were determined.
  • Electrophysiology: Electrophysiological recordings were made from C-fibers to analyze evoked responses to stimulation.
  • Calcium imaging: Intracellular calcium ([Ca²⁺]i) was measured in DRG neurons to assess nociceptor sensitization.

Results

  • Tumor-bearing mice had elevated serum LPA levels, primarily from 18:1-, 18:2-, and 20:4-LPA species.
  • LPA1,3,5 receptor antagonist reduced mechanical and heat hypersensitivity in tumor-bearing mice.
  • ATX inhibitor reduced mechanical and heat hypersensitivity
  • Cancer exosomes increased hypersensitivity in naive mice.
  • Cancer exosomes sensitized nociceptors causing increased spontaneous neuronal activity and reduced mechanical stimulation thresholds.
  • The ATX-LPA-LPAR pathway plays a key role in exosome-mediated hypersensitivity and pain sensitization.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Description

Test your knowledge about the methods used in a recent molecular biology study, including RNA quantification, protein staining techniques, and other experimental procedures. This quiz covers key aspects of the research, from sample types to the roles of team members involved in the study.

More Like This

RNA Detection and Quantification qRT-PCR
12 questions
RNA and Protein Synthesis Flashcards
16 questions
DNA and RNA Structure Flashcards
8 questions
Carga Viral y Detección de ARN
25 questions
Use Quizgecko on...
Browser
Browser