Tag Archives: lung cancer

Mice heavily exposed to e-cig vapor develop lung cancer

Smoking cigarettes is responsible for the vast majority of lung cancers in the world. This terrifying prospect has swayed many smokers to switch to e-cigs, which are thought to be benign in comparison to cigarettes. Vaping, however, is relatively new and there is still much we don’t know about the long-term health consequences. A new study on mice suggests that vaping may also cause lung cancer, for instance.

Credit: Pixabay.

Researchers at New York University performed an experiment in which they exposed mice to two types of vapor. One contained nicotine, emulating the kind of vapor inhaled when using e-cigarettes, the other was a vapor that contained two additives commonly found in e-juice, but no nicotine.

Nine out of the 40 mice exposed to the nicotine vapor developed adenocarcinoma, which is the most common type of lung cancer — that’s an incidence rate of 22.5%. Meanwhile, none of the 18 mice exposed to the e-juice vapor developed lung cancer. One of the 18 mice who weren’t exposed to any type of vapor (the control group) got cancer.

There’s one big caveat to this study — the mice were engulfed in vapor for four hours a day for five days a week. This doesn’t come anywhere close to how e-cigs are actually used in the real world, which caused the study to garner a lot of criticism.

Yet, the study’s methods aren’t necessarily flawed. They show that, albeit in a very extreme case, that there is a very strong connection between nicotine vapor exposure and lung cancer. The findings suggest that e-cigs might cause cancer in some situations — at least it’s an area of research worth pursuing very seriously.

The number of vapers has been increasing rapidly — from about seven million in 2011 to 41 million in 2018, globally. The global market is now estimated to be worth $19.3bn – up from $6.9bn just five years ago.

“Tobacco smoke is among the most dangerous environmental agents to which humans are routinely exposed, but the potential of E-cig smoke as a threat to human health is not yet fully understood,” says Moon-shong Tang, a professor at NYU’s Departments of Environmental Medicine, Medicine, and Pathology. “Our study results in mice were not meant to be compared to human disease, but instead argue that E-cig smoke must be more thoroughly studied before it is deemed safe or marketed that way.”

The new study builds upon the team’s previous work, carried out in 2018, which exposed mice and human cells to e-cig vapor. The researchers reported that e-cig vapor induced DNA mutations linked to lung cancer.

“Our results support the argument that the nicotine-derived DNA adducts are likely the main causes for carcinogenesis in mice exposed to E-cig smoke,” says study author Herbert Lepor, MD, the Martin Spatz Chair of Urology at NYU Langone Health. “Our next step in this line of work will be to expand the number of mice studied, to shorten and prolong E-cigarette exposure time, and to further investigate the genetic changes caused by E-cigarette smoke.”

The findings appeared in the Proceedings of the National Academy of Sciences.

Hookah smoking is becoming more popular, despite health concerns

Although cigarette smoking is on a steady downward curve, a new type of smoking is starting to become more prevalent: hookah.

Alluring and mysterious, the humble hookah packs quite a punch.

Hookah (or shisha) is an instrument for vaporizing and smoking a special type of flavored tobacco. The concept is thought to have originated in medieval India and for centuries, it remained a very niche activity.

In more recent times, however, it has become increasingly popular in many parts of the world, particularly among the youth.

“When I started this research 20 years ago, I did not think that it would be a global problem. Now, hookah has moved to the U.S. and it’s one of the main tobacco products used by young Americans,” says Dr. Wasim Maziak, professor and chair of the Department of Epidemiology at Florida International University in Miami.

Waziak and colleagues found that an estimated 2.6 million US adults (1% of the adult population) smoke hookah in 2017 — nearly double than what was seen in previous years. That’s much lower than the 37.8 million adult smokers in the United States but it’s still considerable — and the kids are smoking it too.

Researchers found that hookah is most common among 18- to 24-year-olds, but it’s also popular among the teens: an estimated 630,000 high school and middle school students smoked hookah in 2017.

This popularity among the youth may be owed to several factors. For starters, it’s associated with the café culture — few people smoke hookah in their own homes, you usually go to a café to smoke it with your friends, which is something that often appeals to youngsters. This also creates the impression that it’s a social activity and not a habit, which can be quite dangerous in the long run. Hookah tobacco is also flavored, usually with fruity flavors which make it much easier to inhale and much more pleasurable to a younger audience.

It’s also quite unique and different compared to other types of smoking. It consists of a head which holds the tobacco, a body of water in a glass chamber beneath it, and a small hose through which you smoke it. The tobacco is warmed using charcoal briquettes. It can be quite an interesting process to watch and follow — it’s quite the show.

However, it’s this exact uniqueness that makes it more dangerous. Hookah smoking essentially creates a pathway between the charcoal and the lungs and a typical hookah session lasts about 30 minutes, much longer than a typical cigarette break.

“This is probably as deadly as cigarettes. For certain carcinogens and toxicants, you have a much higher exposure with waterpipe smoking than cigarettes,” said Maziak.

In fact, a recent 2016 study found that hookah delivers 25 times the tar of a single cigarette, 125 times the smoke, and 10 times the carbon monoxide.

“Our results show that hookah tobacco smoking poses real health concerns and that it should be monitored more closely than it is currently,” said lead author Brian A. Primack, M.D., Ph.D., at the time.

Of course, this is not a perfect comparison because one person might smoke 20 cigarettes a day and only smoke hookah once or twice a week. Nevertheless, it’s a trend that should not be taken lightly. Recently, studies have shown more and more that hookah is becoming more prevalent, with more than 25% of all college students smoking it.

Cigarette smoking is just the most prevalent form of smoking — there are several other alternatives, with various degrees of negative health effects. For instance, electronic cigarettes have also picked up a lot of steam, which was met with mixed reactions because although they do pose health risks, these risks are considerably lower than cigarettes.

Currently, it is unclear if young smokers are aware of the dangers posed by hookah. The practice is relatively new in the Western World.

“There are concerns that hookah smoking could be addicting a new generation of kids, adolescents and young adults who aren’t fully aware of what they are smoking and the relative consequences,” said Mary Rezk-Hanna, an assistant professor at the UCLA School of Nursing.

The CDC has a compelling factsheet about smoking, mentioning among other things that it kills 480,000 Americans every year and is responsible for over 90% of all lung cancer cases.

New treatment boosts survival rates for lung cancer patients

Immune therapy prior to surgery is yielding encouraging outcomes, a new compelling study reports. The innovative treatment has the potential to transform lung cancer treatment.

Huge results

Lung cancer is one of the most dangerous types of cancers out there, but treatment options have become more diverse in recent years. In conjunction with surgery, a new immunotherapy drug shows impressive promise in dealing with the disease.

The drug called Keytruda, or pembrolizumab, is already being used in cancer immunotherapy when tests suggest that patients are likely to respond to it. Keytruda blocks the protective mechanism of cancer cells, allowing the immune system to destroy those cancer cells. In a new study, researchers report that if it is administered prior to surgery, it yields encouraging outcomes that persist for more than one year. The medical team treated 20 patients with immune therapy before surgery, and a year later, 16 of them were alive with undetectable cancer. Two of them were still alive but did still show signs of cancer, while one of the patients died of lung cancer and the last one died of an unrelated head injury. It’s a small study, but results are certainly encouraging.

Results of the new study show that in combination with chemotherapy, the drug is useful for the majority of patients diagnosed with even an advanced form of lung cancer. Furthermore, combinations of immunotherapy drugs can also help people get off the more toxic standard chemotherapy treatment, which improves the life expectancy and the quality of life for patients. The results are so impressive that all lung cancer patients should be given the option of immunotherapy, Dr. Roy Herbst, a lung cancer specialist at Yale Cancer Center who was not involved in the studies, told NBC. Even Dr. H. Jack West, the resident skeptical cancer specialist at the Swedish Cancer Institute in Seattle, says that the results are “huge.”

The study was largely made possible by a collaboration with Stand Up To Cancer (SU2C), a charitable program which aims to raise significant funds for translational cancer research through online and televised efforts, as well as charity shops.

“We were able to achieve this study’s promising results in a relatively rapid time-frame because of the collaboration made possible by our Stand Up To Cancer-Cancer Research Cancer Institute Immunology Dream Team grant,” said senior author of the study Drew Pardoll, MD, PhD, director of Bloomberg-Kimmel Institute for Cancer Immunotherapy and director of Cancer Immunology at Johns Hopkins School of Medicine.

Long-lasting results

The concept of using immunotherapy isn’t really new. The therapy is exciting in the medical community because, in a minority of patients, it reports excellent results even for cancers that have spread throughout the body. However, most of the time, results don’t really persist. Only, this time they do.

“The concept of interception is simple when you hear it, to arrest the natural history of cancer. In other words, once a cancer begins to develop, scientists look for strategic points where they can intervene and stop its growth. This team is using T cells, activated by immunotherapy prior to surgery, to continue to circulate through the patient’s body, after surgery. These T cells can intervene, stopping errant tumor cells from forming new metastases, preventing recurrence,” says Stand Up To Cancer President and CEO Sung Poblete, PhD, RN.

It’s still a small-scale study so results still need to be replicated over a broader sample before we can draw definite conclusions but so far, results are indeed very exciting.

“However, these initial results are highly encouraging and we believe will spur interest in further neoadjuvant clinical trials across additional cancers,” added Dream Team Investigator Patrick Forde, MBBCh, assistant professor of oncology at Bloomberg-Kimmel Institute for Cancer Immunotherapy, who led the study and served as co-principal investigator of the clinical trial.

However, a course of treatment with Keytruda costs $150,000. If the results are indeed confirmed and we start exploring the scalability of the treatment, the price of the treatment also needs to be addressed.

Lastly, it should also be said that the vast majority (85%) of cases of lung cancer are due to long-term tobacco smoking. Aside from tobacco smoking, these cases are also influenced by a combination of genetic factors and exposure to radon gas, asbestos, second-hand smoke, or other forms of air pollution. Prevention is much better and easier than treatment, so if you want to reduce your odds of getting lung cancer, by far the best thing to do is to quit smoking and avoid second-hand smoking.

Journal Reference: Leena Gandhi et al. “Pembrolizumab plus Chemotherapy in Metastatic Non–Small-Cell Lung Cancer,” New England Journal of Medicine. DOI: 10.1056/NEJMoa1801005.

Chinese scientists prepare for first human CRISPR gene-editing trial

Image credit Pixabay

Image credit Pixabay

The CRISPR gene-editing technique has opened up a lot of doors in the scientific world – it has been used to cut out HIV genes from live animals and genetically modify human embryos. Although its benefits are indisputable, experiments such as the latter have caused controversy, as some believe that they bring us closer to changing what it means to be human.

Now, Chinese researchers from the Sichuan University’s West China Hospital have announced their plans to run a clinical trial where CRISPR will be used to modify human beings for the first time ever. In particular, the team plans to work on patients with lung cancer and turn off genes that encode a specific protein linked to a lower immune response.

Although China has come under scrutiny for their promotion of using gene-editing techniques on human beings, the new effort isn’t as controversial as the aforementioned study on human embryos. In fact, a federal panel gave the green light for a similar U.S. study back in June.

“Our goal is to develop a new type of immunotherapy using gene-editing technology that will enable the engineered immune cells to be more potent, survive longer, and thereby kill cancer cells more effectively,” the U.S. team said of their research.

The Chinese clinical trial is set to start next month and will gather T cells, which play a central role in human immunity, from patients with incurable lung cancer and conduct genetic modifications in these cells. These modifications will disable a gene that encodes the PD-1 protein, which has been shown to inhibit the immune response that protects healthy cells from attack.

After the T cells have been successfully modified and examined for editing errors, they will be allowed to multiply and then injected back into the patient’s bloodstream. Ideally, the edited cells will bolster the immune response of the lung cancer patient and aid it in attacking and killing tumor cells.

Thirty candidates are set to participate in the trial, although just one will be injected with a three dose regimen of edited cells, after which the team will monitor the patient for any positive and negative responses to the treatment before proceeding with further trials.

cuban cigar

A lung cancer vaccine made in Cuba will begin clinical trials in the US

Cuba, famous for its rum and cigars, might be one of the unlikeliest places people think of when cutting-edge biotech research is concerned. Despite economic sanctions and embargoes set forth by the US and partners, the country’s medical research institutes boasts some impressive results, particularly in immunization. One prime example is a lung cancer vaccine developed at Cuba’s Center for Molecular Immunology which increases life expectancy by up to six months. Now, the Roswell Park Cancer has signed an agreement with the Cuban medical center to finally bring the vaccine to the US for clinical trials.

cuban cigar

An elderly Cuban man smoking a large cigar on the streets of Havana. Lung cancer is ranked fourth in the leading causes of death list in Cuba. The average life expectancy in Cuba is marginally similar to that in the US. Image: Flickr

Roswell Park will receive all the documentation it needs to begin its trials: toxicity data, how it’s manufactured and results from loads of trials performed in Cuba. The vaccine, called Cimavax, works its magic by kicking the immune system in full gear, such that antibodies might act to kill proteins released by cancerous tumors. As such, the vaccine doesn’t attack tumours directly – which means it doesn’t treat the disease. The antibodies attack a hormone called epidermal growth factor, which typically instructs cells to divide (usually a good thing), but when cancer is around this is undesirable.

Cimavax is given to people who already had contracted cancer, not preemptively like’s the case for most vaccines, effectively keeping the lung cancer from growing too much and metastasizing. This buys time for other methods, like chemo or surgery, to try and treat the disease. The vaccine costs the Cuban government $1 to make and is given to all its sick citizens for free. Lung cancer is the fourth cause of the death in the land of cigars.

Once they try it out and see how it fairs in their own clinical trials – expected to commence one year from now – the Roswell Park researchers want to adapt it to work as traditional vaccine. Namely, as a preventative intervention. Since epidermal growth factors are involved in many other cancers, like  prostate, breast, colon, and pancreatic cancer, the researchers will also explore treatment in these areas as well. Unfortunately, the Cubans were financially restrained to attempt this research themselves.

It’s impressive, however, how much they were able to perform with so little, considering the average wage in Cuba is 20$ per month! At the same time, it gives to show that the stuff of innovation often springs from scarcity. Cuban immunologists have also made their own vaccines for meningitis B and hepatitis B, and monoclonal antibodies for kidney transplants.

“Investigators from around the world are trying to crack the nut of cancer,” says Thomas Rothstein, a biologist at the Feinstein Institute for Medical Research, who has for six years worked with the Center for Molecular Immunology. “The Cubans are thinking in ways that are novel and clever.”

via Wired

lung_cancer

Newly discovered microRNA may help diagnose lung cancer

lung_cancer

Photo: drugdiscovery.com

Researchers at the National Research Foundation of Korea report on Sunday that they have identified a new microRNA molecule that suppresses a gene, which previous research had identified as playing a crucial role in lung cancer development. If the present findings are refined, it may be possible to diagnose lung cancer in the future based on this genetic marker.

MicroRNAs constitute a recently discovered class of non-coding RNAs that play key roles in the regulation of gene expression. Acting at the post-transcriptional level, these fascinating molecules may fine-tune the expression of as much as 30% of all mammalian protein-encoding genes. Their aberrant expression may be involved in human diseases, including cancer, as shown by previous research that found aberrant microRNA is linked to leukemia or breast cancer.

The Korean researchers identified one such  small chain of RNA, called miR-9500, which forms a stem-loop structure and becomes expressed in lower levels in cancer tissue, compared to normal tissue. They also found that miR-9500 directly suppressed Akt1, which is assumed to be its target gene, as demonstrated via western blot, but did not affect the corresponding mRNA levels. Akt1 plays an important role in the production and proliferation of lung cancer genes, the study found.

To prove their point,  Korean scientists infected a mouse with lung cancer and gave it miR-9500 injections over the next six weeks. They found that the rate of metastasis of a tumor in a mouse that had been injected with miR-9500 was significantly lower than that of a tumor growing in a normal mouse.

This sort of investigations will be extremely interesting to follow in the future, especially if a team can come up with a way of viably diagnosing human lung cancer based on miR-9500 expression levels. Already, the research may have some flaws, however. For one, the initial  flank tumor proliferation experiment may be irrelevant, since the flank isn’t the native environment for human cancer cells. Secondly, the researchers performed direct injections into the tumor site with their miR, which kind of defeats the purpose of the experiment – you want to see if the molecule lives long enough in the blood stream until it reaches the target tumor. Then, tumor size sample data wasn’t particularly significant to become extremely valid from a statistical standpoint.

Either way, follow-up studies will be much welcome. The findings were reported in the journal Cell Death and Differentiation.

Study shows dogs can accurately diagnose lung and breast cancer

I recently stumbled across this study which I found absolutely mind blowing. Here’s how researchers did it.

They trained 5 dogs by using a food reward system to recognize, by scent alone, the exhaled breath samples of 55 lung and 31 breast cancer patients from those of 83 healthy controls; once the dogs were trained to do this, their accuracy was just amazing. Among lung cancer patients and controls, the canine sensitivity compared to that of biopsy results was 0.99 (95% confidence interval), and the overall specificity was just as good. Among breast cancer, the results were slightly lower, at 0.88 (95% CI, 0.75, 1.00) and specificity 0.98 (95% CI, 0.90, 0.99). These results were remarkably similar for all stages of the disease, which means they can catch it in the initial stages as well.

The conclusion? Dogs can be used to identify breast and lung cancer with a 95% accuracy, at a fraction of a fraction of the costs of a biopsy. The dogs were trained in a matter of weeks, not even months, so this could actually work as a practical method.

“This pilot work using canine scent detection demonstrates the validity of using a biological system to examine exhaled breath in the diagnostic identification of lung and breast cancers. Future work should closely examine the chemistry of exhaled breath to identify which chemical compounds can most accurately identify the presence of cancer”, the study concluded.

Study bolsters hope for lung cancer pill

A much anticipated and highly expected drug could come from Pfizer Inc, the biggest drug company in the world; the drug appears to double survival over standard approved drugs, but only against lung tumours with a certain mutation. The drug, called crizotinib, would be the first targeted treatment for the roughly 50,000 people who get this cancer each year worldwide, and it would also greatly benefit the pharmaceutical company, producing an annual revenue of over $2 billion.

The twice-a-day pill showed very promising results in studies, ensuring that 3 out of every 4 patients with advanced lung cancer lived past the first year, and over half of them lived after the second year; this, even if it is sad to say, are indeed very promising results.

Dr. Alice Shaw, a Mass. General oncologist who was also the lead researcher in this project explained how this treatment works by basically turning off an enzyme which stimulates the growth and mantains the survival of the cancer cells; without that enzyme, the cancer dramatically slows down, allowing the body to regain strength, and there are even hopes of total remission.

Lung cancer is responsible for 1.3 million deaths anually; in the US alone, some 30.000 people are diagnosed with lung cancer each year, and out of them, about 14 percent live past the five year mark. Of course, smoking is the main cause of the disease, accounting for over three quarters of the victims.

Lung cancer may be detected with a cheek swab

It is always better to prevent than to treat, but when you have no other choice but treatment, the absolute best thing you can do is treat it early.However, by the time the first symptoms appear, it is often too late to do anything. Thus, helping victims cope with it is very difficult as it seems to have come out of nowhere.

Detecting cancer in its early stages often makes the difference between life and death and early detection is directly related to the cancer survival rates. Researchers from Northwestern University and NorthShore University HealthSystem (NorthShore) have recently developed a method that relies on a pioneering technique (biophotonic) to detect early signs of lung cancer.

Lung cancer is well known for being extremely difficult to pinpoint, but with this method, the problem can be solved; what they do is basically shine diffuse light on cells swabbed from patients’ cheeks.

“By examining the lining of the cheek with this optical technology, we have the potential to prescreen patients at high risk for lung cancer, such as those who smoke, and identify the individuals who would likely benefit from more invasive and expensive tests versus those who don’t need additional tests,” said Hemant K. Roy, M.D., director of gastroenterology research at NorthShore.

The breakthrough technique is called partial wave spectroscopic (PWS) microscopy and was developed by Vadim Backman, professor of biomedical engineering at Northwestern’s McCormick School of Engineering and Applied Science. Lung cancer is not only hard to detect, but it’s also causes a lot of victims; in the US, it is the leading cause of cancer deaths, and survival rates are high only when detected early. However, by the time the first symptoms appear, it is often too late to do anything.

Still, PWS shows great promise; it can detect cells as small as 20 nanometers and uncover differences that appear normal with standard microscopy techniques.

“Despite the fact that these cells appear to be normal using standard microscopy, which images micron-scale cell architecture, there are actually profound changes in the nanoscale architecture of the cell,” Backman said. “PWS measures the disorder strength of the nanoscale organization of the cell, which we have determined to be one of the earliest signs of carcinogenesis and a strong marker for the presence of cancer in the organ.”

“PWS is a paradigm shift, in that we don’t need to examine the tumor itself to determine the presence of cancer,” added Hariharan Subramanian, a research associate in Backman’s lab who played a central role in the development of the technology.

The lung cancer findings are published only by Cancer Research, and the printed paper will appear on Oct 15.

Note: This article is not intended to provide treatment, diagnosis or medical advice in any way.