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Showing posts with label Oncology. Show all posts
Showing posts with label Oncology. Show all posts

Tuesday, February 13, 2018

Some Breast Cancers Fail to Respond to Treatments, Why?


Most breast cancers are estrogen receptor-positive, meaning that signals received from estrogen, a hormone, promote the growth of the tumors. To stop these cancers from spreading, estrogen inhibitors are usually prescribed. But what happens when tumors develop treatment resistance?


Studies suggest that "approximately 70 percent" of all the breast cancers are estrogen receptor-positive (ER-positive).

These types of cancer are typically treated with drugs — such as tamoxifen and fulvestrant — that either lower the levels of the hormone or inhibit the estrogen receptors to prevent the tumors from spreading. This is known as endocrine therapy.

However, around a third of the people treated with these drugs develop resistance to them, which negatively impacts their chances of survival. The mechanisms that underlie the tumors' resistance to therapy is not well understood and currently poses a major challenge.



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.


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

Wednesday, September 20, 2017

FISHing in the Genomic Testing Age !

Genetic analysis has come a long way; we now have an ever-expanding collection of analytical tools in the diagnostic laboratory. So why do we still need a technique that usually only looks at one or two loci? The simple answer is that results from fluorescence in-situ hybridization (FISH) can quickly confirm diagnoses, guide clinicians’ judgements regarding differential diagnoses, and correlate results with clinical risk—thus enabling an informed choice of treatment type and intensity.

FISH employs fluorescently-labeled DNA probes to bind complementary DNA sequences within an interphase cell, or onto metaphase chromosomes. These sequences can then be visualized using fluorescent microscopy. The number, location and relative positions of the probe signals indicate chromosomal changes in a particular cell (Figure 1).

Many clinical trials use cytogenetic and FISH data to stratify patients according to specific risk factors. FISH is often used as a stand-alone technique for investigating abnormalities and following-up such patients, which, alongside its relatively low expense, makes it a very convenient investigative tool.

In this article we will explore the utility of FISH in today’s clinical laboratory and the future of the technique in the evolution of molecular testing.

Figure 1. The FISH process.
Figure 2. Interphase cell showing amplified HER2 signal pattern.





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

Cervical Screening of ‘Limited’ Use in Under 25s

The National Cervical Screening Program (NCSP) has been successful for the most part, except for those aged 20-24, according to a new report from Cancer Council NSW.

Incidence of squamous cell carcinoma and overall cervical cancer rates have declined dramatically in women aged 25-plus since the inception of the program in 1991.

“Squamous cell cancer rates in women aged 25 years or more fell by more than 50% but have now plateaued among women aged 25-69 years,” writes Megan Smith and Professor Karen Canfell in the MJA.

But among those aged 20-24, screening has made no difference to cancer rates.



Source: 6minutes

Saturday, October 15, 2016

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.

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.

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.

Friday, September 2, 2016

The Laser Probe, The iKnife, and The Cutting Edge of Surgery

If the thought of going under the knife fills you with fear, be reassured. No longer is surgery the brutal and hazardous experience faced by our ancestors. Thanks to wonders such as laparoscopy, robotic solutions, and, more recently, the iKnife and the laser probe, surgical intervention is getting safer all the time.

Archaeologists believe that people have been carrying out surgery for up to 11,000 years. Cranial surgery, known as trephination, probably dates back to the Neolithic era. It involved drilling a hole in the skull of a living person.

Speculation suggests it was done to cure disorders such as convulsions, fractures, headaches, and infections. The Ancient Egyptians used the same operation for "letting out" headaches and migraine.


Technological advances make surgery safer and more precise all the time. In robotic surgery, the surgeon
controls the instruments from a console. MRI-guided surgery shows where the tumor is, but the iKnife
can detect its exact borders.

Friday, August 5, 2016

Throat Cancer: Get the Facts

The throat is often described as having many different parts. This article looks at two of the more common places throat cancer can occur: the pharynx and the larynx.
  1. The pharynx is most commonly thought of as the throat. It is a tube around 5 inches long that leads from behind the nose to the food pipe.

  2. The larynx is also known as the voicebox. It is a short passage just below the pharynx. The larynx holds the vocal cords and a small piece of tissue called the epiglottis.
The epiglottis moves to cover the top of the larynx so food cannot enter it when people breathe.


Cancer in the throat is uncommon when compared with other forms of cancer. Early symptoms of
throat cancer include a long-lasting cough and pain when swallowing.

Tuesday, July 26, 2016

Colorecal Cancer: Minimally Invasive, Triple-Therapy Patch Destroys Tumors

Research released by the Massachusetts Institute of Technology describes an adhesive patch that can deliver a triple-combination of drug, gene, and light-based therapy to colorectal tumors.

Colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. The lifetime risk of developing colorectal cancer is 1 in 21 for men and 1 in 23 for women.

Most colorectal cancers begin as a growth, or tumor, on the inner lining of the colon or rectum called a polyp, and they can change to cancer over many years. Not all polyps become cancer.

It usually takes around 10-15 years for abnormal cells to grow into colorectal tumors. With regular screening, polyps can be removed before they develop into cancer.

Although the type of treatment for colorectal cancer largely depends on the stage of cancer, treatment options are often surgery, chemotherapy, and radiation therapy.


The triple-therapy patch could be used to treat any remaining cancer cells at the tumor site after surgery.

Friday, July 15, 2016

H. Pylori: Know the Facts

Helicobacter pylori, commonly called H. pylori, is a type of bacteria that can infect the stomach and small bowel. It was discovered in 1982 by two Australian researchers who found that it causes peptic ulcer disease.

Peptic ulcers are open sores in the lining of the stomach or the upper part of the small intestine. Peptic ulcers are often called "ulcers" or "stomach ulcers."

For years, medical experts believed that peptic ulcers were caused by stress or certain foods. After the discovery of H. pylori, however, this belief was put to rest. A study in Digestive and Liver Disease suggests that 60 to nearly 100 percent of peptic ulcers are associated with H. pylori.


H. pylori bacteria attack the protective lining of the stomach, causing ulcer, that can be diagnosed
with an endoscopy.

Thursday, July 7, 2016

Prostate Cancer And DNA Mutation: New Connections Revealed

Specific mutations in the DNA of men with metastatic prostate cancer have been shown to play a larger role in the disease than previously thought. Researchers hope that this finding will help change standard therapy guidelines and open the door to drugs currently being used for other cancers.

The new study, published in the New England Journal of Medicine, examined inherited mutations in DNA repair genes.

These gene mutations were already known to occur more frequently in prostate cancer patients than the general population.

However, the present study demonstrated that mutations in DNA repair genes were even more prevalent in people with metastatic prostate cancer, specifically.


Gene mutation research gives a new perspective on prostate cancer.

Sunday, July 3, 2016

Eating Walnuts May Help Prevent Colon Cancer

A team of researchers from UConn Health and The Jackson Laboratory for Genomic Medicine found that eating walnuts can reduce one's risk of getting colon cancer.

In the study, mice that were fed walnuts (totaling seven percent to 10.5 percent of their total calories) developed fewer instances of colon cancer.

Seven to 10.5 percent of daily total calories coming from walnuts is equivalent to a human eating about an ounce of walnuts every day.

Walnut consumption
"Our results show for the first time that walnut consumption may reduce colon tumor development," said Daniel W. Rosenberg of UConn Health, principal investigator on the study.


Could walnuts be the key to preventing colon cancer?

Friday, July 1, 2016

'Breast Cancer Gene' BRCA1 Linked to Aggressive Uterine Cancer

Mutations in women's BRCA genes, which are linked to both breast cancer and ovarian cancer, may also increase their risk of developing a particularly deadly form of uterine cancer, a new study finds.

The BRCA1 and BRCA2 genes are sometimes referred to as the "breast cancer genes" because women who have a mutation in one or both of these genes face a much greater risk of developing breast and/or ovarian cancer than women without mutations in these genes.

But previous studies have also suggested that women with a BRCA1 or BRCA2 mutation may also be more likely to develop a type of uterine cancer called uterine serous carcinoma, said Dr. Noah Kauff, director of clinical cancer genetics at the Duke Cancer Institute in North Carolina and the senior author of the new study.


SebastianKaulitzki | Shutterstock
Source: livescience

BRCA1 Gene Mutation May Raise Risk of Aggressive Endometrial Cancer

The risk of aggressive serous or serous-like endometrial cancer may be higher for women with a BRCA1 gene mutation, even after undergoing risk-reducing surgery involving the removal of the fallopian tubes and ovaries. This is the finding of a new study published in JAMA Oncology.

However, the study found that a mutated BRCA1 gene did not increase women's overall risk of uterine cancer if they had undergone the risk-reducing procedure, called risk-reducing salpingo-oophorectomy (RRSO).

RRSO is the surgical removal of the fallopian tube and ovaries, and it is sometimes recommended for women who are at high risk of breast or ovarian cancers as a result of BRCA1 or BRCA2 gene mutations.


Researchers say women with a BRCA1 mutation are at higher risk for aggressive endometrial cancer,
even after undergoing risk-reducing surgery.
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