cancer development

Is There a Link Between Fungal Infections and Cancer Development?

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Addressing fungal infections may offer a novel means to help prevent cancer in the immunocompromised.

Is There a Link Between Fungal Infections and Cancer Development?

Some researchers are looking for innovative ways to fight cancer. One novel approach may involve addressing fungal infections.

According to a 2021 study published in Advanced Pharmaceutical Bulletin (APB), epidemiological evidence shows a clear link between fungal infections and cancer development. Researchers frequently find this association in people who are immunocompromised, such as those with AIDS.

Why Might the Connection Between Cancer and Fungal Infections Be Relevant?

In 2018 18.1 million new cases of cancer occurred worldwide, with 9.5 million lives lost to it. Experts predict the number of new cases will soar to 29.5 million by 2040 and cancer-related deaths to 16.4 million. In an attempt to reduce the ever-rising rates of incidence, some scientists are exploring the risk factors that underlie the disease.

According to the APB study, cancer has a broad array of risk factors including microbial infection, obesity, diet, sex and nation, lifestyle, smoking, alcohol consumption, and exposure to environmental pollutants.

A 2020 study published in Microbial Pathogenesis found that microbial infections underlie about 20 percent of all cancers. Of this 20 percent, a portion may stem from fungal infections.

The APB study states that the most common fungi species involved in cancer include:

  • Candida albicans
  • C. tropicalis
  • C. glabrata
  • Fusarium verticillioides
  • F. proliferatum
  • Aspergillus flavus
  • A. parasiticus

How Do Fungal Infections Increase Cancer Risk?

The APB study explains that fungal infections produce cancer-causing chemicals that include:

  • Acetaldehyde: This harms DNA and prevents repair of the damage. The greater the exposure to acetaldehyde, the higher the cancer risk.
  • Mycotoxins: These are fungal metabolites that cause adverse health effects, including chromosomal changes and a risk of cancer.
  • Nitrosamine: These are chemicals that can damage chromosomes or DNA and have tumor-producing effects.
  • Proinflammatory cytokines: These chemicals indicate inflammation. They influence cancer development in multiple ways.

Who May Get Fungal Infections?

Anyone can get a fungal infection. While many types of fungi do not usually cause infections in healthy individuals, they are more likely to produce them in those with weakened immunity. The below factors may make it more difficult to fight a fungal infection:

Certain Health Conditions

This includes HIV or AIDS, especially in those with a CD4 (a type of white blood cell that plays a role in immunity) count of less than 200. Stem cell or organ transplants also make fighting fungal infection more difficult due to the immunosuppressive drugs taken to prevent organ rejection.

A Stay in a Health Care Facility

The use of medical devices, such as ventilators and catheters in hospitals or skilled nursing facilities create opportunities for fungi to enter the body. Candida auris frequently spreads among people in health care settings. Candida auris can be spread through contact with infected people and contaminated equipment or surfaces in health care settings.

Older Age

A decline in immunity is a well-known effect of aging, thus, fighting off fungal infections is more challenging for older adults.

Medications That Affect Immunity

This includes oral and inhaled corticosteroids, which are used to treat asthma, allergies, arthritis, and autoimmune diseases. Anti-inflammatory drugs such as TNF inhibitors used to treat autoimmune diseases, chemotherapy, and radiation therapy also weaken the immune response.

What Antifungal Interventions Are Available?

Doctors may recommend prophylactic treatment for fungal infections for people with weakened immunity. Prophylaxis in this context refers to taking antifungal medications to help prevent infections, instead of waiting until infections manifest to start treatment.

Fungi are a natural part of the environment, so it is hard to avoid them. They are present in soil and outdoor vegetation, as well as on the skin and many indoor surfaces. The following measures may reduce exposure to fungi:

  •  Stay away from areas with lots of dust, such as construction sites.
  • Avoid areas with bird and bat droppings, such as chicken coops and caves.
  • Wear shoes, long-sleeved shirts, and long pants when engaging in outdoor activities.
  • Wear gloves when handling manure, moss, or soil.

What Natural Agents Have Antifungal Properties?

Although antifungal medications are available, they can have side effects. In addition, drug-resistant fungal strains are emerging. Consequently, researchers are looking for alternatives to synthetic drugs that come from natural compounds. The below options show promise:

Garlic

Studies have found that many fungi species are sensitive to garlic. The antifungal mechanisms of action in garlic include:

  • Suppressing the synthesis of nutrients fungi need, such as proteins and fats.
  • Reducing their growth.
  • Damaging their cell membranes.
  • Decreasing their oxygen uptake.

Other studies note that garlic contains more than 100 biologically active compounds, most of which contain sulfur. A main sulfur compound, ajoene, has “important” antifungal activity against both yeast and non-yeast forms of fungi.

Curcumin

Curcumin is a compound found in the spice turmeric that contains powerful antifungal properties. Curcumin suppresses fungi growth by disrupting their synthesis of vital enzymes and proteins.

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Another study discovered that curcumin was more effective than the antifungal drug fluconazole in inhibiting the attachment of candida species to cells inside of the cheek, particularly in people with AIDS.

Propolis

Propolis is a mixture of beeswax and pollen that bees collect from certain plants. Studies found that it contains 26 or more constituents with antifungal properties. Researchers propose that the main mechanism of action underlying its properties stems from the ability to induce apoptosis, or cell death, in fungi.

A Final Word

Although many individuals with cancer have fungal infections, it does not mean that the infections cause the cancer.

However, the authors of the APB study express concern, as they note that the infections “may play a significant role in the risk for precancerous lesions.” With this in mind, it seems reasonable to think that efforts to prevent fungal infections in people with compromised immunity are worthwhile.

How a bad night’s sleep might worsen cancer development

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Recent studies have indicated that patients with sleep apnea may be associated with worse cancer outcomes. Now a new animal study, presented at the European Association of Urology Congress in Munich, uncovers a possible mechanism which may underlie this link.

Hypoxia is where a tissue or organ does not get enough oxygen. It is one of the consequences of sleep apnea, which is a common disorder in which you have one or more pauses in breathing or shallow breaths while you sleep. Sleep apnea has been associated with increases in the risk of several conditions, such as high blood pressure or stroke. Recently some evidence has also linked it to worse cancer outcomes, although there is some conflicting evidence on this. The possible mechanism linking apnea to worse outcomes is not known, although it is known that patients suffering from obstructive apnea usually suffer from intermittent hypoxia.

Now a group of Spanish-US researchers have used a mouse model to show that intermittent hypoxia promotes the formation of blood vessels within tumours, probably due to an increased production of Vascular endothelial growth factor (VEGF). VEGF is known to promote blood vessels formation.

A team led by Dr Antoni Vilaseca (Hospital Clínic De Barcelona, Spain) took 12 experimental and 12 control mice with kidney tumours and subjected them to varying oxygen levels to mimic intermittent hypoxia. They found that the mice which had been subjected to intermittent hypoxia showed increases in vascular progenitor cells (6,1 ± 0,76 vs 4,5±1,1; p=0,001) and endothelial cells (4±0,8 vs 2,5±1; p=0,013) within the tumors; these cells may later mature to form blood vessels in the tumors. Circulating VEGF was also increased in the mice which had undergone hypoxia (306±93 vs 204±45 pg/mL; p=0,001), although other factors such as tumour growth, were not affected.

Lead researcher Dr Vilaseca said:

“Patients suffering from obstructive sleep apnea usually suffer from intermittent hypoxia at night. This work shows that intermittent hypoxia has the potential to promote the formation of blood vessels within tumours, meaning that the tumours have access to more nutrients”.

He continued

“This is of course an early animal study, so we need to be cautious in applying this to humans. Nevertheless, this work indicates a plausible mechanism for just why conditions which restrict oxygen flow to tissues, like sleep apnea, may promote cancers”.

Commenting, Professor Arnulf Stenzl (Tübingen), Chair of the EAU Congress Committee, said:

“Although this is an experimental study, it is remarkable, because it demonstrates the influence of oxygen deficiency on the growth of renal cell carcinoma tissue (both primary tumour as well as metastases). It may be postulated that increased oxygenation of the blood may be the underlying mechanism why not smoking or giving up smoking, regular sport activity (especially endurance type sports), reducing the body mass index and other life style changes that increase tissue oxygenation have a supportive beneficial effect on better outcomes in renal cell cancer as well as other tumour types”.

An orgasm a day could keep prostate cancer at bay

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Men in their forties who orgasm every day are much less likely to develop the disease, according to researchers at Harvard Medical School.

Doctor discussing prostate cancer with patient

For men in their forties, a daily orgasm can reduce the risk of developing prostate cancer by over 20 per cent, according to new research.

The study, conducted by Harvard Medical School, followed nearly 32,000 healthy men over 18 years, almost 4,000 of whom went on to develop prostate cancer.

Researchers found that men in the 40-49 age range who ejaculated at least 21 times per month were 22 per cent less likely to develop the disease than those who ejaculated between four and seven times per month.

Dr Jennifer Rider of Harvard Medical School said that “While these data are the most compelling to date on the potential benefit of ejaculation onprostate cancer development, they are observational data and should be interpreted somewhat cautiously.”

Last year, a study carried out researchers at the University of Montreal concluded that men who had sex with more than 20 women were 19 per cent less likely to develop the most aggressive form of prostate cancer.

However, when lead researcher Dr Marie-Elise Parent was asked whether public health authorities should recommend men to sleep with many women in their lives, she commented: “We’re not there yet.”

Each year in the UK around 41,000 men are diagnosed with prostate cancer and 11,000 die from the disease.

Last month it was reported that a new treatment, called “chemoimmunotherapy“, could wipe out the disease in its advanced form by boosting the body’s immune system.

Rare kidney tumor provides insights on role of metabolic changes in cancer

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Researchers in The Cancer Genome Atlas (TCGA) Network have made a number of new findings about the biology and development of a rare form of kidney cancer. They found that the disease – chromophobe renal cell carcinoma (ChRCC) – stems in part from alterations in genes in the mitochondria, the cell’s energy supplier. They also discovered that the tumor is characterized by genetic rearrangements near a gene important in DNA repair and in maintaining telomerase, the enzyme which determines a cell’s lifespan. Finally, investigators also found that ChRCC is a distinct disease and shares few genomic characteristics with other kidney cancers.

In the study – the most extensive genomic view of ChRCC to date – investigators led by Chad Creighton, Ph.D., Baylor College of Medicine, Houston, and Kimryn Rathmell, M.D., Ph.D., University of North Carolina, Chapel Hill, performed a complex array of analyses, including examining the entire genomes of 50 of the 66 ChRCC tumors studied, a high number for a rare cancer. The study revealed increased numbers of mitochondria as well as mutations in mitochondrial DNA. This led researchers to discover that ChRCC tumors favor a different energy-generating process than that used by the more common clear cell kidney cancer. In addition, their findings are the first to show specific alterations affecting the TERT gene that could affect cancer development, and might help explain its increased expression – and deregulation – in cancer. Overall, the findings provide new insights into the development of more common forms of kidney cancer, and shed light on the role of mitochondria and metabolic pathways in cancer. The results also support the growing realization that both the cancer’s genomic characteristics and cell of origin matter, as many cancers consist of several individual diseases that require specific therapies. TCGA is a collaboration jointly supported and managed by the National Cancer Institute (NCI) and the National Human Genome Research Institute (NHGRI), both parts of the National Institutes of Health.Cancer Cell.

– See more at: http://www.noodls.com/view/D6600F38EB21D71D5B39925086E0D042FDD339A5?2286xxx1408677428#sthash.G8WbrQQ4.dpuf