What is Mesothelioma?
A particular form
of cancer known as mesothelioma appears in the lining that protects
several of the body's organs' external surfaces. Typically, asbestos
exposure is the cause. Although it can damage the lining of the stomach
(peritoneal mesothelioma), heart, or testicles. Mesothelioma primarily
affects the lining of the lungs (pleural mesothelioma). In the UK, the
illness is identified in more than 2,600 persons annually. Most cases are
discovered in patients between 60 and 80, and men are more frequently impacted
than women. Unfortunately, mesothelioma is rarely curable, though
treatment can help manage the symptoms.
What is Asbestos mesothelioma?
Lung cancer,
asbestosis, and asbestos mesothelioma are all well-known occupational
illnesses. As industrial asbestos use declines, para-occupational,
environmental, and natural exposures to asbestos are more common in the general
population. Communities such as Broni, Italy; Libby, Montana; Wittenoom,
Western Australia; Karain, Turkey; Ambler, Pennsylvania; and others have shown
asbestos mesothelioma clusters. Community asbestos mesotheliomas provide unique
public health problems and difficulties. Community exposure causes higher
proportions of mesothelioma in women and a younger age distribution than
occupational exposures. Asbestos mesothelioma expression is influenced by
exposure quantity, age at exposure, fibre type, and genetic predisposition;
at-risk individuals include those with social and behavioral issues, exposure
to traumatic experiences, and genetic predispositions. Regulations should cover
all elongated mineral fibers that are carcinogenic in order to address
population exposure. A ban on asbestos mining, usage, and imports won't lessen
the existing problems associated with asbestos. Residents of high-risk areas
are typically exposed through various channels between communities. Compared to
workplaces, administrative duty for limiting environmental exposures is more
dispersed, made more challenging by the disparate attitudes to asbestos
mesothelioma risk and prevention among communities and the complexity of the
law. The identification of communities at risk is aided by the National
Mesothelioma Registries. Enhanced screening, diagnosis, treatment, and social
and psychological support, including retired asbestos workers, are needed in
high-risk communities. Legal settlements may be used to support neighborhood
programs. It is advised to emphasize preventive and public health initiatives,
customization to individual community requirements, and involvement.
How does asbestos cause Mesothelioma?
Diffuse malignant mesothelioma
in humans has been linked to inhaling asbestos fibers. The disease's carcinogenic
processes are still unknown, despite developments in the molecular analysis of
human mesothelioma and the creation of animal models. Regarding the
pathophysiology of asbestos-induced mesothelioma, there are
primarily three hypotheses, which can be summed up as follows:
(1) The
"oxidative stress theory" contends that asbestos fibers cause
chromosome damage when cells divide and that iron-containing asbestos fibers
appear more carcinogenic. (2) The "chromosome tangling theory"
contends that asbestos fibers cause chromosome damage due to their
inability to be digested by phagocytic cells. (3) The "theory of
adsorption of many specific proteins as well as carcinogenic" For the
creation of fresh methods to stop Mesothelioma induction in those who
have already been exposed to asbestos, elucidating the main mechanisms
behind mesothelioma would be beneficial.
Does asbestos always cause mesothelioma?
Asbestos exposure
most of the time causes mesothelioma. However, there is still a sizable
part of the population with mesothelioma with no proof of occupational exposure
to asbestos. Although a significant risk of pleural mesothelioma owing
to asbestos exposure is confirmed. Most of these instances may be caused
by various asbestos exposure sources, primarily household or environmental.
How much asbestos can cause mesothelioma?
Asbestos fibers
that are long and thin have a higher potential for mutagenesis and
cytotoxicity. According to a meta-analysis, people who are exposed to fibers
longer than 10 micrometers or even 20 micrometers have a significantly higher
risk of developing an asbestos-related Mesothelioma. This is because longer
asbestos fibers are more difficult for macrophages to effectively engulf and
remove, which results in repeated attempts at phagocytosis failing. Reactive
oxygen species (ROS) and reactive nitrogen species (RNS) are released by the
inflammatory cells surrounding the asbestos fibers as a result of the ensuing
"frustrated phagocytosis," which has mutagenic effects.
Why does asbestos cause mesothelioma?
According to the
"oxidative stress theory," asbestos fibers appear to be cancer-causing
because they damage chromosomes during the cell cycle.
Is asbestos the only cause of mesothelioma?
In the Western
World, almost 80% of malignant mesotheliomas occur in people with higher than
average asbestos exposure. Only a tiny percentage of people exposed to
asbestos develop mesothelioma, suggesting that other factors are involved.
Several human mesotheliomas have been found to include Simian virus 40 (SV40),
a DNA tumor virus that preferentially produces mesothelioma in hamsters. The
ability of antisense T-antigen therapy to inhibit mesothelioma cell growth in
vitro and the expression of the SV40 large tumor antigen in mesothelioma cells
but not in surrounding stromal cells imply that SV40 contributes to tumor
development. A causal role for SV40 in the pathogenesis of mesothelioma is
supported by the ability of T-antigen to bind and inhibit cellular p53 and
retinoblastoma (Rb)-family proteins in mesothelioma as well as by the highly
high susceptibility of human mesothelial cells to SV40-mediated transformation
in vitro. In vitro human mesothelial cell transformation by SV40 appears to be
amplified by asbestos, indicating that SV40 and asbestos may both be
carcinogenic. While p16, p14ARF, and NF2 mutations/losses are frequently
detected in mesothelioma, p53 mutations are infrequent. In the Anatolian
villages of Karain and Tuzkoy in Turkey, recent investigations found the
presence of a genetic component that predisposes affected persons to mesothelioma.
In these communities, where mesothelioma is the cause of 50% of deaths,
erionite, a form of zeolite, may be a contributing factor.
Asbestos and
erionite, among other environmental carcinogens, ionizing radiation, viruses,
and genetic factors, all appear to have a role in the development of
mesothelioma.
Summary
In the 1950s,
malignant mesothelioma was recognized as a novel disease. It is virtually
always brought on by asbestos exposure and is typically detected decades after
the initial exposure. Asbestos workers were the only one
s who could get the
disease at first. Still, diagnoses following non-workplace exposure are on the
rise. Even though all forms of asbestos are carcinogenic and have been recognized
as such by the World Health Organization (WHO) and the International Agency for
Research on Cancer (IARC) more than 40 years ago, global asbestos use increased
exponentially, leading to an almost universal presence of these minerals in
homes, commercial buildings, ships, vehicles, and thousands of other products.
