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Showing posts with label Cancer. Show all posts
Showing posts with label Cancer. Show all posts

Friday, June 1, 2018

What is a free PSA test and what is it for?


"The free prostate-specific antigen test, known as the free PSA test, is used to help detect signs of prostate cancer. The test measures the level of unbound prostate-specific antigen in the blood, which can help doctors to diagnose issues like inflammation of the prostate or cancer."
Free PSA tests are often used alongside other PSA tests to confirm a diagnosis or test results. Free PSA tests can also be used instead of a biopsy if the doctor suspects prostate cancer, but a biopsy may still be needed.


This article examines when a free PSA test is used, how it differs from a total PSA test, and what the results mean.

Saturday, January 27, 2018

Study Sheds Light on How High Cholesterol Causes Cancer !



New research from the University of California, Los Angeles has found a previously unknown molecular mechanism involving cholesterol that may promote tumor growth in the intestines.

A report on the study — published in the journal Cell Stem Cell — reveals how increasing levels of cholesterol in mice increased proliferation of intestinal stem cells and made tumors grow faster.

One of the methods that the researchers used to increase the availability of cholesterol to intestinal cells in the mice was to feed them a high-cholesterol diet.

"We were excited to find," says senior author Peter Tontonoz, a professor of pathology and laboratory medicine, "that cholesterol influences the growth of stem cells in the intestines, which in turn accelerates the rate of tumor formation by more than 100-fold."



He and his colleagues believe that their findings could pave the way to new treatments for gastrointestinal diseases, such as colon cancer.




Sunday, January 14, 2018

Cancer Transcriptome Profiling at the Juncture of Clinical Translation !




Methodological breakthroughs over the past four decades have repeatedly revolutionized transcriptome profiling. Using RNA sequencing (RNA-seq), it has now become possible to sequence and quantify the transcriptional outputs of individual cells or thousands of samples. These transcriptomes provide a link between cellular phenotypes and their molecular underpinnings, such as mutations. In the context of cancer, this link represents an opportunity to dissect the complexity and heterogeneity of tumours and to discover new biomarkers or therapeutic strategies. Here, we review the rationale, methodology and translational impact of transcriptome profiling in cancer.





Transcriptomics is the large-scale study of RNA molecules by use of high-throughput techniques. It examines the abundance and makeup of a cell's transcriptome. In contrast to DNA, which is largely identical across all cells of an organism, the actively transcribed RNA is highly dynamic, reflecting the diversity of cell types, cellular states and regulatory mechanisms. Because a transcriptome profile can be regarded as a signature or snapshot of the underlying cell state, the experimental profiling of samples and specimens can provide insights into their unique biology.

Depending on the specific approach, transcriptomics can not only reveal the architecture of gene expression but also provide details on the structure, modification and variation of individual transcripts. Advances in transcriptome profiling, specifically the development of genome-wide methodologies targeting diverse RNA species, have enabled us to discover the seemingly endless complexity of RNA biology and to comprehensively annotate the human genome and other eukaryotic genomes. Arguably, transcriptomics is currently the most well-established modality and foundation of functional genomics, a field of study for which the goal is to synthesize large-scale data to understand the mechanisms that govern cellular and organismal phenotypes.
  • RNA sequencing (RNA-seq) has the potential to bridge tumour genotypes (for example, mutations) and their phenotypic consequences (for example, cancer molecular subtypes).
  • The field of transcriptomics has matured thanks to lockstep developments in experimental protocols, algorithms and databases.
  • Methodological and algorithmic advances continue to enable clinical applications of transcriptome profiling.
  • Detection of gene fusions is the most immediate application of RNA-seq.
  • Gene expression signatures have demonstrated prognostic and predictive value.
  • Transcriptome profiling will be essential for immuno-oncology.


Wednesday, December 6, 2017

Transcriptional Regulation by Mediator Complex


Alterations in the regulation of gene expression are frequently associated with developmental diseases or cancer. Transcription activation is a key phenomenon in the regulation of gene expression.

In all eukaryotes, mediator of RNA polymerase II transcription (Mediator), a large complex with modular organization, is generally required for transcription by RNA polymerase II, and it regulates various steps of this process. The main function of Mediator is to transduce signals from the transcription activators bound to enhancer regions to the transcription machinery, which is assembled at promoters as the preinitiation complex (PIC) to control transcription initiation.




Recent functional studies of Mediator with the use of structural biology approaches and functional genomics have revealed new insights into Mediator activity and its regulation during transcription initiation, including how Mediator is recruited to transcription regulatory regions and how it interacts and cooperates with PIC components to assist in PIC assembly.

Novel roles of Mediator in the control of gene expression have also been revealed by showing its connection to the nuclear pore and linking Mediator to the regulation of gene positioning in the nuclear space. Clear links between Mediator subunits and disease have also encouraged studies to explore targeting of this complex as a potential therapeutic approach in cancer and fungal infections.


Key points

  • Recent structural advances based on improvements in electron microscopy methodology have enabled the generation of high-resolution structural models of the mediator of RNA polymerase II transcription (Mediator) complex and of the preinitiation complex (PIC) in the presence of Mediator.
  • The module composition of Mediator changes between its recruitment to upstream regulatory regions (enhancers or upstream activating sequences where Mediator is bound to transcription factors) and its action on core promoters together with PIC components.
  • The functional interplay between Mediator and general transcription factors in PIC assembly is closely related to chromatin architecture at promoter regions.
  • Direct contact between Mediator and the nuclear pore-associated transcription-coupled export (TREX2) complex suggests that Mediator functions in gene positioning in the nuclear space.
  • Mediator has been shown to function in the establishment of transcriptional memory, which also involves Mediator interactions with the nuclear pore.
  • Potential therapeutic targeting and modulation of Mediator activity in cancers and in fungal infectious diseases emphasizes the importance of studies of Mediator mechanisms for improving human health.




Monday, October 16, 2017

Causes of High PSA that are not Cancer !

The prostate-specific antigen test is a blood test that measures levels of a protein the prostate gland produces. Men with prostate cancer usually have elevated levels of this protein, but heightened levels do not always mean cancer.

Other health conditions may also cause prostate-specific antigen (PSA) levels to rise. In some cases, an elevated PSA is temporary and not a sign of a health problem at all.

Cells in the prostate gland produce PSA and levels typically remain below 4 nanograms per milliliter (ng/mL).

Most men with prostate cancer have PSA levels above 4 ng/mL, but about 15 percent of men with a PSA level below 4 ng/mL are also diagnosed with prostate cancer. This means that a PSA test alone cannot rule out or diagnose prostate cancer but can identify whether a man is at higher risk of having or developing the disease.

Initial testing may include both a PSA test and a digital rectal exam (DRE). During this examination, a doctor inserts a finger into the rectum to check the prostate for abnormalities. Together, if these two tests suggest prostate cancer, then the doctor will arrange for a biopsy to confirm the diagnosis.

False positives - a high PSA level, but no cancer - on the PSA test are common. PSA levels rise with age and other factors. Men with high PSA levels should follow up with a doctor, but should not assume they have cancer.


A high PSA level may not always indicate prostate cancer.




Source: MedicalNewsToday






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Thursday, September 21, 2017

Tumor Marker Tests Overused in Primary and Secondary Care !

A tumor marker is a biomarker found in blood, urine, or body tissues that can be elevated by the presence of one or more types of cancer. The vast majority of tumor marker tests in primary and secondary care may not be necessary as the tests assisted with a cancer diagnosis in just 2% of patients.

Tumor markers are molecules, which may be present in higher than usual concentrations in the tissue, serum or other body fluids of patients with cancer. There are many different tumor markers, each indicative of a particular disease process, and they are used in oncology to help detect the presence of cancer. A tumor marker can be used to aid diagnosis in specific situations but testing for more than one marker is not recommended.

Scientists at South West Wales Cancer Centre (Cardiff, UK) examined the number of multiple tumor marker requests from primary and secondary care over a six-month period within Abertawe Bro Morgannwg University Health Board (Bagain, Neath Port Talbot, Wales). Multiple requests were defined as more than one tumors marker for a patient in a two-week period. The team looked at how many patients with multiple tumor markers measured were subsequently diagnosed with cancer, and whether the markers assisted with the diagnosis.


Common tumor markers used in the diagnosis of cancer




Source: LabMedica

Saturday, February 25, 2017

Gene Editing Could Help Tackle Cancer And Inherited Diseases

Gene editing techniques developed in the last five years could help in the battle against cancer and inherited diseases, a University of Exeter scientist says.

"There is always a risk with this kind of technology and fears about designer babies and we have started having discussions about that so we can understand the consequences and long-term risks," said Dr Westra, of the Environment and Sustainability Institute on the University of Exeter's Penryn Campus in Cornwall. "I think in the coming decades gene editing will become super important, and I think we will see it being used to cure some inherited diseases, to cure cancers, to restore sight to people by transplanting genes. I think it will definitely have massive importance."

On Tuesday, two highly influential academic bodies in the US shook up the scientific world with a report that, for the first time, acknowledged the medical potential of editing inherited genes. The National Academy of Sciences and National Academy of Medicine ruled that gene editing of the human "germline"—eggs, sperm and embryos—should not be seen as a red line in medical research.



Source: medicalxpress

Friday, February 17, 2017

How Body Fat May Make You More Prone to This Cancer

Most of the time people try to lose a few pounds so they like that reflection in the mirror a little more, but it turns out the benefits of weight loss may extend well beyond looking better in your swimsuit.

A new study suggests that, if you’re an older woman, shedding excess pounds may also reduce your risk of developing endometrial cancer, a potentially deadly disease with which tens of thousands of women are diagnosed each year.


A close-up image of a slim young woman with a belly fat after giving birth. Woman's torso with
some belly fat. Abdominal fat.

Wednesday, November 23, 2016

MicroRNA: A Tiny Molecule Yields Big Insights Into Disease States

Regular readers of this column will know that there are two main categories of nucleic acids—DNA and RNA. They’ll also know that while for living organisms DNA acts as the genetic data repository, RNA has a messenger role (mRNAs, transcribed from DNA to direct protein synthesis). Most will also recall that there are other classes of RNA molecules, particularly tRNAs (used to tag and identify amino acids for protein synthesis) and rRNAs (structural components of the ribosome, the cellular “machinery” for protein synthesis). In addition to these, there’s increasing interest in the molecular diagnostics community in a less widely known but no less common RNA form, the microRNA or miRNA.



Sunday, October 16, 2016

Cancer Awareness Month

With a broken heart 💔 and tears 😢 in my eyes, nothing is more painful than trying to smile and remain positive, but after many tests, being poked and prodded, chemo and radiation, the person physically changes and they suffer with sadness. I know many of you do not give a hoot about this message because, of course, the cancer has not affected you. You do not know what it's like to have fought the fight, or have a loved one who leads or has led a battle against cancer. 💜

For all the men and women I know, I ask you a small favor- I know only some of you will do it. If you know someone who has led a battle against cancer, still struggling, or who passed, please add this to your status for one hour as a mark of support, respect, and remembrance. 💚 ❤️

Copy and paste to support those affected by cancer. Do Not Share. From your phone or tablet, hold your finger on the message to copy and paste.


Source: Facebook

Saturday, October 15, 2016

Unnecessary Endoscopies Could Be Avoided with Fecal Blood Test

The majority of primary care patients referred for bowel endoscopy do not have significant colorectal disease (SCD), and are unnecessarily exposed to a small but realistic risk of severe endoscopy-associated complications.

Serious colorectal diseases, including colorectal cancer, are difficult to diagnose as the signs and symptoms are not always clear.


The Quantum Blue rapid test allow for the immediate measurement of fecal calprotectin
(Photo courtesy of Bühlmann Laboratories).
Source: LabMedica

What Does Breast Cancer Feel Like? Lumps and Pain Explained

In breast cancer, abnormal genes cause breast cells to grow uncontrollably and not die off as they normally would.

If these cells grow slowly and don't invade other tissues, they cause benign tumors. These are lumps that are not usually considered dangerous to health.

When abnormal cells grow at a more rapid rate and begin to invade surrounding tissues, they form cancerous tumors. These lumps pose a serious risk and can spread, creating new tumors throughout the body.


When breast cancer first appears, it can cause a wide range of different symptoms. Always seek
medical attention if in doubt about possible breast symptoms. Breast cancer can also affect men.

Monday, October 3, 2016

From 230,000 patients to extinct in 15 years: pathology and new drugs key to defeating hepatitis C

An estimated 230,000 Australians have chronic hepatitis C, and a quarter of cases are undiagnosed.

Hepatitis C inflames the liver and unlike the A and B viruses there is no vaccine available. Pathology is important for diagnosing the virus.

Many people with hepatitis C may not experience symptoms, but left untreated the disease can cause cirrhosis (scarring of the liver), which in a small number of cases can lead to liver cancer.


Source: knowpathology

Sunday, September 25, 2016

Swarms of Magnetic Bacteria Could be Used to Deliver Drugs to Tumors

One of the biggest challenges in cancer therapy is being able to sufficiently deliver chemotherapy drugs to tumors without exposing healthy tissues to their toxic effects.

Researchers funded in part by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) have recently shown that magnetic bacteria are a promising vehicle for more efficiently delivering tumor-fighting drugs. They reported their results in the August 2016 issue of Nature Nanotechnology.


Illustration showing magnetic bacteria delivering drugs to a tumor.
Source: LabManager

Thursday, September 22, 2016

Cancer: Shutting Down Fat Synthesis In Cancer Cells Stunts Tumor Growth

Tumors have a voracious appetite for fat and rely on hastened fat synthesis in cancer cells to satisfy their need. Now, a new study shows it is possible to use drugs to shut down fat synthesis in cancer cells to stunt tumor growth without harming healthy cells.

A report on the study is published in the journal Nature Medicine.

The discovery - by researchers at the Salk Institute in La Jolla, CA, and collaborators - represents a new frontier in the search for targeted treatments against cancer, a leading cause of disease and premature death worldwide.


The researchers found cells treated with a placebo produced more fat (red, on left) than cells treated
with the enzyme inhibitor (right). Image credit: Salk Institute

Friday, September 16, 2016

Cancer: Four-Stranded DNA Could Help Develop Targeted Treatments

By taking a closer look at four-stranded versions of DNA inside the genome of human cells, scientists have discovered some potential new avenues for targeted cancer treatments. They found that the quadruple helix structures occur in DNA regions that control genes, especially cancer genes.

The researchers, from the University of Cambridge in the United Kingdom, report their findings in the journal Nature Genetics.

Targeted cancer therapies are currently the focus of much research and development into new anticancer treatments.

They are an important area of precision medicine - where information about an individual patient's genes and proteins are used to prevent, diagnose, and treat disease.


The aim of targeted therapy is to attack cancer cells without affecting healthy cells.

'Tracking Bugs' Reveal Secret of Cancer Cell Metabolism

One of the hallmarks of cancer is a change in cellular metabolism, a series of chemical reactions so fundamental to life that their alteration makes cancer cells seem creepily malevolent.

Healthy cells take in blood sugar (glucose molecules), which they break down to extract energy. This happens in two phases—one phase that takes place in the cytoplasm and a subsequent phase that occurs inside cellular compartments called mitochondria.

Cancer cells are thought to mostly skip the mitochondrial phase, compensating for the energy they forgo by revving up the first phase and breaking down glucose rapidly to secrete large quantities of lactate—a form of partially digested glucose that has long been regarded as a "waste product.


Metabolism is nothing if not complicated. Some of the major metabolic pathways are shown in this
metro-style map.
Source: phys.org

Monday, September 12, 2016

Melanoma May Be Stoppable With Drug That Halts Cancer Cell Proliferation

A drug already being tested in people as a treatment for cancer appears to show great promise in halting melanoma skin cancer. The drug - called pevonedistat - works in a way differently than intended and could also be effective against other cancers.

So says a new study from the University of Virginia School of Medicine in Charlottesville that was published in the journal EBioMedicine.

Lead researcher Tarek Abbas, assistant professor of radiation oncology, says:

"In fact, the drug is very effective on all melanomas, including those for which an effective therapeutic is lacking."

Melanoma is an aggressive skin cancer that develops when melanocytes - the cells that give skin its color - mutate and become cancerous.


Melanoma is an aggressive skin cancer that develops when cells that give skin its color mutate and
become cancerous. The researchers say they have found a drug that may stop the cancer progressing.

Monday, September 5, 2016

Liver Cancer Risk Influenced By Blood Selenium Levels

The risk of developing liver cancer may be significantly higher for people who have low levels of the nutrient selenium in their blood, suggests a new study published in the American Journal of Clinical Nutrition.

Selenium is a trace mineral present in soil, animal products, and plant-based foods, including seafood, Brazil nuts, organ meats, milk, and eggs.

The selenium content of food varies greatly, as it depends on how much of the element is in the plants animals consume, as well as how much is in the soil in which plants grow.

According to the National Institutes of Health (NIH), selenium is essential for human health, with beneficial roles for reproduction, the immune system, and DNA synthesis.

Studies have also shown that selenium has antioxidant properties, meaning it can protect against oxidative stress - the process by which uncharged molecules called free radicals damage cells.


Low blood selenium levels may put people at greater risk of liver cancer.

Sunday, September 4, 2016

Amino Acids in Cancer Metabolism and Neuroscience

These Building Blocks Could Be Valuable Tools for Research

Amino acids are important building blocks for protein synthesis and are also intermediary metabolites that fuel biosynthetic reactions, thus playing a dual role in cellular metabolism. Accurate quantification of L-amino acids in body fluids or purified samples may provide valuable information for diagnostic and basic research studies.

Cellular Roles of Amino Acids in Cancer and Neurobiology
Cancer cells have altered metabolism and are known for their metabolic abnormalities. One example is the Warburg effect, in which there is increased glycolytic activity even in the presence of oxygen. Cancer cells depend on a high rate of aerobic glycolysis for continued growth and survival.


Figure 1. Glutamine and the metabolism of other amino acids as targets for cancer therapy.
[Int J Mol Sci 2015;16:22830–22855; doi:10.3390/ijms160922830]
Source: genengnews
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