Researchers have developed a simple and versatile method for making artificial anti-cancer molecules that mimic the properties of one of the body’s natural defence systems.
The chemists, led by Professor Peter Scott at the University of Warwick, UK, have been able to produce molecules that have a similar structure to peptides which are naturally produced in the body to fight cancer and infection.
Published in Nature Chemistry, the molecules produced in the research have proved effective against colon cancer cells in laboratory tests, in collaboration with Roger Phillips at the Institute for Cancer Therapeutics, Bradford, UK.
Artificial peptides had previously been difficult and prohibitively expensive to manufacture in large quantities, but the new process takes only minutes and does not require costly equipment. Also, traditional peptides that are administered as drugs are quickly neutralised by the body’s biochemical defences before they can do their job.
A form of complex chemical self-assembly, the new method developed at Warwick addresses these problems by being both practical and producing very stable molecules. The new peptide mimics, called triplexes, have a similar 3D helix form to natural peptides.
Behold the mighty mushroom. Neither plant nor animal, the mysterious fungus is a class, or kingdom, of its own, and has fascinated cultures around the world for centuries. But while they do make a tasty omelette filling, does the real magic of mushrooms lie not in their flavour, but in their potential to combat one of our biggest killers – cancer?
The ancient Egyptians believed eating mushrooms brought long life. While their scientific method was perhaps not entirely sound, modern scientists investigating the medicinal properties of the organism are beginning to produce some fascinating results. There are thousands of species of mushroom growing in the wild, but most studies have focused on three main varieties – reishi, maitake and shiitake.
Reishi, otherwise known as ganoderma, has been used in Chinese medicine for 2,000 years and numerous studies have investigated its much-vaunted anti-cancer and immune-boosting properties. In a paper published last year in the US’s Proceedings of the National Academy of Sciences (PNAS) journal, a team of scientists linked its use to cancer-cell death. The team, from the Taiwanese research centre Academia Sinica, found that F3 polysaccharides, a type of carbohydrate molecule found in reishi mushrooms, can induce antibodies to recognise and kill antigens associated with tumours or cancer cells.
A lot of animals have an amazing sense of smell, so they can often pick up things that even sensitive odor sensing machines might miss. We already know that dogs and even bees have an impressive ability to sniff out diseased cells, but now a group of scientists in Germany have genetically modified fruit flies so their antennae glow if they smell cancer cells.
Led by Dr. Giovanni Galizia, the team from the University of Konstanz in Germany discovered that not only could the fruit flies tell cancerous cells from healthy ones, they were also able to separate out five individual lines of breast cancer cells. This shows that the fruit flies have a much keener sense of smell than even those cancer sniffing dogs, although I must admit that fruit flies aren’t nearly as cute or cuddly.
Unlike some dogs, fruit flies aren’t exactly great at communicating with humans, so the researchers needed to give the tiny insects a way to signal when they smelled trouble. To create an indicator, Dr Galizia’s team developed a genetically mutated variant of the little guy, where its antennae would take on fluorescent properties if as little as a single molecule carrying the odor hit the fly’s receptors.
Dr. Galizia is confident that the fruit fly will eventually become standard equipment in oncologist offices, allowing for earlier cancer detection than any of the current methods both man-made and canine. They’d just better make sure that they stash those fruit flies away before the cleaning lady arrives shaking a can of Raid.
South Korean scientists say they have developed the world’s first nanorobot that can selectively target and help treat cancer. The robot is guided through the body by genetically engineered bacteria to a tumor where it releases its cargo of cancer fighting drugs.
Stanford researchers are on track to begin human trials of a potentially potent new weapon against cancer, and would-be participants are flooding in following thePost’s initial report on the discovery. The progress comes just two months after the groundbreaking study by Dr Irv Weissman, who developed an antibody that breaks down a cancer’s defense mechanisms in the body.
A protein called CD47 tells the body not to “eat” the cancer, but the antibody developed by Dr Weissman blocks CD47 and frees up immune cells called macrophages — which can then engulf the deadly cells. The new research shows the miraculous macrophages effectively act as intelligence gatherers for the body, pointing out cancerous cells to cancer-fighting “killer T” cells. The T cells then “learn” to hunt down and attack the cancer, the researchers claim.
“It was completely unexpected that CD8+ T (killer T) cells would be mobilized when macrophages engulfed the cancer cells in the presence of CD47-blocking antibodies,” said MD/PhD student Diane Tseng, who works with Dr. Weissman.
The clinical implications of the process could be profound in the war on cancer. When macrophages present “killer T” cells with a patient’s cancer, the T cells become attuned to the unique molecular markers on the cancer.
This turns them into a personalized cancer vaccine.
“Because T cells are sensitized to attack a patient’s particular cancer, the administration of CD47-blocking antibodies in a sense could act as a personalized vaccination against that cancer,” Tseng said. The team of researchers at Stanford plan on starting a small 10-100 person phase I clinical human trial of the cancer therapy in 2014.
Researchers at the University of Missouri have found a way to create radioactive nanoparticles that target lymphoma tumor cells wherever they may be in the body.
Michael Lewis, an associate professor of oncology in the MU College of Veterinary Medicine, says being able to target secondary tumors is vital to successfully treating patients with progressive cancers.
“Depending on the type of cancer, primary tumors usually are not the cause of death for cancer patients,” Lewis said. “If a cancer metastasizes, or spreads creating hard-to-find tumors, it often becomes fatal. Having a way to identify and shrink these secondary tumors is of utmost importance when fighting to save people with these diseases.”
In an effort to find a way to locate and kill secondary tumors, Lewis, in collaboration with J. David Robertson, director of research at the MU Research Reactor and professor of chemistry in the College of Arts and Science, have successfully created nanoparticles made of a radioactive form of the element lutetium. The MU scientists then covered the lutetium nanoparticles with gold shells and attached targeting agents.
The ability of cells to move and change shape is significant in many biological processes. White blood corpuscles gather at “hotspots” like infections and inflammations. Stem cells in the embryo move off in different directions to make the organs of the body. One unwanted movement is the movement of tumour cells, which lead to cancer metastasis.
Cells have a clear leading and trailing edge and move by a broad, thin membrane protrusion shooting out in front while the rest of the cell follows it. Small, finger-like filopodia (the green parts of the human renal cell pictured at left) can also project out from the protrusion, probably a type of cellular antenna that senses the chemical environment – bacterial secretions, for example.
But what governs this ability to move? Water, say the Linköping research team, who set out their hypothesis in the scientific journal PLOS One.
For a cell to be able to initiate a movement there needs to be a complex interaction between the outer cell membrane and the cytoskeleton on the inside. One of the most important components is the protein actin, which has the ability to create dynamic fibres that can grow at one end and recede at the other. The current thinking is that, in this way, the membrane can push out and create the protrusions. But experiments and modelling have led the LiU researchers to another picture of the mechanism.
“We looked at how cells create the membrane protrusions they need in order to be able to move. We showed that the water flow out of and into the cells through water channels, or aquaporins, in the cell membrane is important,” says Thommie Karlsson, researcher in medical microbiology and principal author of the article.
Researchers have long known that the gene, p16INK4a (p16), plays a role in aging and cancer suppression by activating an important tumor defense mechanism called “cellular senescence.”
A team led by Norman Sharpless, Professor of Cancer Research at University of North Carolina, has developed a strain of mice that turns on a gene from fireflies when the normal p16 gene is activated. In cells undergoing senescence, the p16 gene is switched on, activating the firefly gene and causing the affected tissue to glow.
Throughout the entire lifespan of these mice, the researchers followed p16 activation by simply tracking the brightness of each animal. They found that old mice are brighter than young mice, and that sites of cancer formation become extremely bright, allowing for the early identification of developing cancers.
“With these mice, we can visualize in real-time the activation of cellular senescence, which prevents cancer but causes aging. We can literally see the earliest molecular stages of cancer and aging in living mice,” says Sharpless, who is also the Deputy Cancer Center Director.
An experimental “Trojan-horse” cancer therapy has completely eliminated prostate cancer in experiments on mice, according to UK researchers.
The team hid cancer killing viruses inside the immune system in order to sneak them into a tumour.
Once inside, a study in the journal Cancer Research showed, tens of thousands of viruses were released to kill the cancerous cells.
Experts labelled the study “exciting,” but human tests are still needed.
Using viruses to destroy rapidly growing tumours is an emerging field in cancer therapy, however one of the challenges is getting the viruses deep inside the tumour where they can do the damage.
“The problem is penetration,” Prof Claire Lewis from the University of Sheffield told the BBC.
She leads a team which uses white blood cells as ‘Trojan horses’ to deliver the viral punch.
After chemotherapy or radiotherapy is used to treat cancer, there is damage to the tissue. This causes a surge in white blood cells, which swamp the area to help repair the damage.
“We’re surfing that wave to get as many white blood cells to deliver tumour-busting viruses into the heart of a tumour,” said Prof Lewis.
A magnetic method of killing cancer cells has been developed by scientists in South Korea.
The technique uses a magnetic field to flip a “self-destruct” switch in tumours.
Researchers have demonstrated that the process works in bowel cancer cells and living laboratory fish. Programmed cell death, or apoptosis, is one of the body’s ways of getting rid of old, faulty or infected cells.
In response to certain signals, the doomed cell shrinks and breaks into fragments. These are then engulfed and consumed by amoeba-like immune cells.
Often in cancer, apoptosis fails and cells are allowed to keep dividing uncontrollably.
The magnetic therapy involves creating tiny iron nanoparticles attached to antibodies which bind to “receptor” molecules on tumour cells. When the magnetic field is applied, the molecules cluster together, automatically triggering the “death signal” that sets off apoptosis.
Sometimes stepping back and looking at the big picture can lend new clarity to an ongoing debate. In this case, it took the distant perspective of astrobiologists to reckon the origins of cancer.
The astrobiologists, working with oncologists in the US, have suggested that cancer resembles ancient forms of life that flourished between 600 million and 1 billion years ago.
The genes that controlled the behaviour of these early multicellular organisms still reside within our own cells, managed by more recent genes that keep them in check.
It’s when these newer controlling genes fail that the older mechanisms take over, and the cell reverts to its earlier behaviours and grows out of control.
Scientists from Maryland’s Johns Hopkins University, in conjunction with Danish researchers, have developed a drug using a Mediterranean weed that can target tumor cells and destroy them.
The extraordinary drug travels undetected through the bloodstream until it encounters a tumor cell, where it is activated by specific proteins. It destroys the tumor cells, neighboring cancer cells, and the blood vessels that act as their supply, but spares healthy cells and blood vessels.
The drug, called G202, was tested on mice and the study was led by Samuel Denmeade, MD, professor of oncology, urology, pharmacology and molecular sciences at Johns Hopkins University. Over the course of 30 days, the human prostate tumors grown in mice were reduced by an average of 50 percent. In comparison tests with the chemotherapy drug docetaxel, G202 reduced eight of nine tumors by more than 50 percent over the course of 21 days. Docetaxel reduced only one of the nine tumors in the same amount of time.
G202 also provided the same results for human models of bladder, kidney, and breast cancers.
An artificial “brain” built by a 17-year-old whiz kid from Florida is able to accurately assess tissue samples for signs of breast cancer, providing more confidence to a minimally invasive procedure.
The cloud-based neural network took top prize in this year’s Google Science Fair.
“I taught the computer how to diagnose breast cancer,” Brittany Wenger, the Lakewood Ranch resident, told me today.
“And this is really important because currently the least invasive form of biopsy is actually the least conclusive, so a lot of doctors can’t use them.”
Wenger wanted to create a way for more doctors to use the minimally invasive procedure, called Fine Needle Aspirate, in order to ease the process of having lumps examined.
Breast cancer affects one in eight women worldwide, she noted, including members of her family.
“Early detection is really important,” Wenger said. “And that is what I’m trying to do with my neural network.”
Researchers at Case Western Reserve University School of Medicine have discovered a mutant form of the gene, Chk1, that when expressed in cancer cells, permanently stopped their proliferation and caused cell death without the addition of any chemotherapeutic drugs. This study illustrates an unprecedented finding, that artificially activating Chk1 alone is sufficient to kill cancer cells.
Researchers have revealed how a molecule called telomerase contributes to the control of the integrity of our genetic code, and when it is involved in the deregulation of the code, its important role in the development of cancer. The University of Montreal scientists involved explain how they were able to achieve their discovery by using cutting edge microscopy techniques to visualize telomerase molecules in real time in living cells inMolecular Cell on December 9, 2011.
“Each time our cells divide, they need to completely copy the genomic DNA that encodes our genes, but the genome gets shorter each time until the cell stops dividing,” said Dr. Pascal Chartrand, a biochemistry professor at the University of Montreal and a senior author of the study. “However, the telomerase molecules can add bits of DNA called telomeres to the ends of our genome. Telomeres prevent the genome from deteriorating or joining up with other pieces of DNA, allowing cells to divide indefinitely and become cancerous. Normally, the telomerase gene is not active, but how it is controlled is poorly understood. One difficulty has been that we need to see exactly what individual telomerase molecules are doing on our genome and when.” Franck Gallardo, the study’s lead author, added that the team was able to apply techniques from other work that the team was doing in their lab. “We could in fact visualize what individual telomerases were doing in cells,” he said.