microrna research to advance cancer diagnostics
One day, in the not too distant future, some of you will be able to have a straightforward minimally invasive blood test for early diagnosis of cancer during a visit to your family doctor. Although this is not yet a reality in the clinical setting, many recent advances and technological breakthroughs have already made it possible in the laboratory to accurately detect early stage lung cancer in patients on the basis of a blood sample. What's more, very recent developments in cancer therapeutics will mean that some current cancer patients may be able to benefit from an entirely new class of cancer treatments, that are based on miRNA chemistry (see further down for details on clinical trials).![]() |
For info about Biozantium by Paeon Laboratories: http://www.biozantium.com |
Discovery of blood-based miRNA biomarker signature
Dr Wozniak, a cancer researcher who is a specialist in molecular epidemiology, presented her latest laboratory findings on early cancer detection in plasma samples (blood plasma is the pale yellow liquid fraction that is obtained after centrifugation of a blood sample) whilst attending the American Association for Cancer Research (AACR) Annual meeting 2014.![]() |
Dr Magdalena Wozniak presented her most recent
laboratory findings at the American Association for Cancer Research (AACR) Annual Meeting 2014. |
Given that
only a minute quantity of miRNAs is present in a “straightforward” minimally invasive
liquid biopsy of body fluids (e.g. cerebrospinal fluid or blood), development
of this assay was anything but straightforward, particularly, when taking into
consideration the governing complexities that determine the sensitivity and robustness of
tests used in the diagnosis of lung cancer on the basis of microRNAs. As such, equipment, protocols, and bioinformatics analysis tools had to be optimised in order to accurately detect these lung cancer associated microRNA signatures.
Importance of accurate early lung cancer detection
This new development in early detection assays for lung cancer is incredibly important as it can literally make the difference between life and death. The 2014 WHO World Cancer Report, documents nearly 1.6 million lung cancer deaths per year world-wide (by far the highest number of cancer deaths caused by a specific type of cancer). This level of mortality is thought to be due to the late stage at which this cancer is usually detected.
Hence, even
though this technology will not yet be available in the clinic, the development
of tests that can make very early stage cancer detection a reality should be
welcomed. Early detection of cancer is the ultimate goal (particularly in lung
cancer), as early detection could save many lives. The earlier a cancer is
detected, the more treatment options are available to the patient and the less
debilitating the aftermath is likely to be.
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miRNA biomarker diagram visualising process of minimally invasive
blood test for early diagnosis of cancer.
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Dr Wozniak and colleagues are not
the only ones searching for biomarkers that can accurately diagnose early stage
lung cancer. A number of renowned cancer centres are working towards this “holy
grail” of early cancer detection, and includes groups investigating cell free
DNA (cfDNA) / circulating tumor DNA (ctDNA) diagnostic biomarkers.
The other reason this is such a
pressing matter is because when you have a very early stage tumour (e.g. stage
1 tumor), you will feel healthy. A patient with such a tumour is unlikely to
present him- or herself to the doctor, because he or she is still actively
engaged in daily live (e.g. exercising, running errands, etc…) without any sort
of feeling that something's wrong (a patient is likely to be unaware of his or
her condition until it is literally too late). The blood test that has been developed by Dr Wozniak and her colleagues will be able to detect lung cancer at
a very early stage, and could perhaps be introduced as a routine test to
increase early stage detection rates.
Cost of early detection in vitro diagnostics (IVD) tests offset
While some people may argue that these types of new medical technologies will drive up the cost of care, it is likely that these cancer blood tests will in fact do the opposite, when they are made available for a few hundred dollars / Euros within the next few years. Ultimately, it could help patients avoid costly scans, and perhaps most importantly avoid late-stage diagnoses, when cancer is often more difficult and more expensive to treat.
Although, these researchers have
come up with a novel and exciting minimally invasive cancer test, they also council
caution for too much optimism while they conduct an Independent prospective
validation of the clinical potential of the panel within a cohort with pre-diagnostic
samples.
Please note: Any medical or scientific information published on this website is not intended as a substitute for informed medical advice from a physician and you should not take any action before consulting with a health care professional. For more information, please read my terms & conditions.
When and where can you expect gain access to microRNAs that are used to treat cancer?
While it is outside the scope of the research performed by the above mentioned
authors, it is perhaps useful to explain in a brief summary how microRNAs can be
exploited for not just diagnosing cancer but also for the treatment of cancer
and what the future may hold in this regard.
![]() |
Timeline illustrating breakthrough discoveries in the field of miRNA
research with a primary focus on discoveries and inventions that
have had an impact on cancer.
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The observation
that specific cancer types have particular microRNA signatures associated with
them (based on research using surgically resected tissue samples) has led
certain biotech companies to develop microRNA profiling arrays that enable
clinical labs to characterise a malignant metastatic cancer and establish with a
high degree of accuracy what the primary site of such a tumour is. It is
these types of microRNA profiling experiments that can determine a patient’s
outlook on the basis of specific microRNA profiles, and it is likely that more
of these types of tests and assays will enter clinics in the near future (e.g.
tests which are in development for establishing the characteristics of
different tumour types include: specific ovarian and uterine cancers that are
particularly difficult to distinguish histologically).
However, utilising the
therapeutic potential of microRNAs in the mainstream cancer care is still some
way off, although a limited number of human clinical trials are currently being
prepared (e.g. a multi-centre
phase-I clinical trial where the safety, Pharmacokinetics and Pharmacodynamics
of the micro ribonucleic acid (microRNA) MRX34, in patients with inoperable
primary liver cancer or advanced or metastatic cancer with liver metastasis is
studied and a clinical
study that aims to assess the safety and efficacy of gemfibrozil in modulating
microRNA-107 levels for the prevention of Alzheimer's disease).
Different types of microRNA - two sides of the same coin
As discussed earlier, it
is known that in many different cancer types, particular microRNAs get
up-regulated or overexpressed. A select number of scientists are currently
trying to identify ways that will allow for targeting, and knocking-down of
these “oncogenic” microRNAs in a clinical setting. Systematically knocking-down
microRNAs has already been established in pre-clinical mouse models as being a
feasible procedure in cancer therapeutics. Importantly, these drugs are
apparently well tolerated in humans. It is likely that more phase I and phase
II clinical trials will be set up in the near future to investigate antisense
molecules that can target such oncogenic microRNAs.
However, in many cancer
types, specific microRNAs have reduced expression levels (these are so-called
tumour suppressor microRNAs). When these types of microRNAs are eliminated
tumours form more readily inside your body. Re-introducing these types of
microRNAs back into your body is an approach that is also actively being
investigated (including microRNAs as well as microRNA mimetics (molecules that
resemble microRNA and can act as a superior surrogate for the tumour suppressor
microRNA).
Outlook for microRNA therapeutics
Ultimately, a combination
of both strategies (a therapy in which oncogenic microRNAs are knocked down and
levels of tumour suppressor microRNAs are restored) is most likely to result in
a more durable response.
One important aspect to
note with regards to using microRNAs as a therapeutic intervention is the fact
that these RNAs are natural products made from your genes and have a long
evolutionary history in all living things (including humans). This is also
likely the reason why scientists investigating these molecules have not seen
any strong side effects when microRNAs have been administered in pre-clinical
studies.
In summary, microRNA based diagnostics or therapeutics within a clinical setting holds great promise for the future in the
treatment of various types of cancer as well as other diseases.
Please note: Any medical or scientific information published on this website is not intended as a substitute for informed medical advice from a physician and you should not take any action before consulting with a health care professional. For more information, please read my terms & conditions.
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