Molecular Pathology and Personalized Medicine | Role of Biomarkers & Genetics

Introduction

The field of modern medicine is in a deep transformation that occurred due to the incorporation of molecular science in the field of medicine. Historically, diagnosis and treatment were conducted on observable symptoms, imaging and histopathological analysis. These approaches though effective in most cases, were usually general and failed to consider the variability of different individuals in disease progression or response to treatment.

This has been altered with the introduction of molecular pathology. There is a larger quantity of diagnostic instruments, predictive biomarkers, and treatment, because the area under investigation examines molecular and genetic disease pathways. Molecular pathology is not just another branch of laboratory medicine- the principle of individual medicine, which is seeking to take into account the treatment on the basis of a separate patient pathological profile, through the application of an individual molecular pattern.

The article covers the history of molecular pathology, methodology, clinical application of the procedure, and its radiant impact on personalized medicine. It also examines issues, ethical issues as well as the trend that will shape the field in the future.

Understanding Molecular Pathology

Definition and Scope

Molecular pathology is the pathology of the molecules and genes. The word molecular pathology (in contrast to traditional pathology) is used to denote the studies of DNA, RNA and proteins alterations leading to pathophysiologic process.

Its scope includes:

• Determination of genetic mutation and polymorphisms.
• Identifying infectious organisms in molecular tests.
• Quantifying gene and protein patterns.
• Using molecular diagnostics in disease classification and treatment recommendations.

Evolution of the Field

The molecular disease rests on the observation of the double helix structure of the DNA in 1953 and the ensuing invention of genetic testing.  This has modified the occupation, such as the next-generation sequencing (NGS), fluorescence in situ hybridisation (FISH), and polymerase chain reactions (PCR).

The interface between the fields of genetics and genomics and clinical medicine, between patient care and research, has formed a new niche in the molecular pathology.

Key Techniques in Molecular Pathology

Polymerase Chain Reaction (PCR)

PCR permits the amplification of a large DNA portion and, consequently, enables the identification of minute quantities of genetic material. It was extensively applied in infectious disease identification, genetic defect and cancer biomarkers identification.

Next Generation Sequencing (NGS)

NGS facilitates massive sequencing of full genome or a collection of genes. It also possesses much information about the genetic variations and is able to properly diagnose and select treatment.

Fluorescence In Situ Hybridization (FISH)

In the detection of chromosomal abnormalities, FISH is applied and this is referred to the use of fluorescent probes. It can also be used in diagnosis of genetic syndromes, cancer like leukemia.

Immunohistochemistry (IHC)

IHC is both a molecular and morphological technique that involves antibodies to identify a given protein in a sample tissue. It is important in cancer subtyping and targeted therapy.

Microarrays and Transcriptomics

The process of simultaneously identifying the expression of thousands of genes to get information about disease process, or even drug response is referred to as microarray assessment.

Biomarkers: The Language of Molecular Pathology

Diagnostic Biomarkers

These determine the existence or non-existence of a disease. This is one of the situations whereby in the event of breast cancer, there is the presence of the HER 2 overexpression which identifies a special type of cancer which will need special treatment.

Prognostic Biomarkers

These are used to predict the probable path or the same of a disease. Indicatively, there are TP53 tumour mutations that are aggressive.

Predictive Biomarkers

These show the probability of response to a given therapy. EGFR mutations predict sensitivity to tyrosine kinase inhibitors in the case of lung cancer.

Personalized medicine concerns the biomarkers that are applied in customizing the modifying one to all treatment approach to treatment to the individual treatment approach.

Clinical Applications of Molecular Pathology

Oncology

Most benefited areas of molecular pathology have been in cancer care. Tumour genomic profiling allows the detection of driver mutations and guides the application of targeted therapies.

• Trastuzumab is valuable in breast cancer patients whose cancer cells have been found to have amplified HER2.
• ALK rearrangements in non-small cell lung cancer patients respond to ALK inhibitors.
• The liquid biopsies identify tumour DNA in the blood that offers non-invasive analysis of the progression of the disease.

Genetic Disorders

Molecular diagnosis is a type of diagnosis that determines genetic defects of a genetic disease e.g. cystic fibrosis (CFTR gene) or Huntington disease (HTT gene). Early screening, preventive health care, genetic counsel and informed family planning is a possibility.

Infectious Diseases

Molecular diagnostics is required to diagnose pathogens in a timely and adequate manner. PCR-based tests have revolutionized the treatment of infectious diseases; HIV, hepatitis, and COVID-19.

Pharmacogenomics

This subdivision of molecular pathology examines how genetic variations affect drug metabolism. It also causes personalized prescription since it foresees adverse reactions or effectiveness of the therapy. As an illustration, a patient with CYP2C19 polymorphisms will be in need of alternative antiplatelet medications.

Molecular Pathology in Personalized Medicine

Tailored Treatments

Molecular profile usage in a way that helps individuals in choosing what type of treatment is more appropriate can be defined as personalized medicine. Instead of general treatments, clinicians can treat individuals with genetic variations.

Improved Outcomes

Personalised treatments achieve the maximum patient responsiveness in treatment, drug reaction undermining and enhanced survival due to the removal of the critical pathogenesis of the disease.

Real time Monitoring

The molecular assays that might be employed to track the progression of the disease and the effect of the treatment on it would be the liquid biopsies. The dynamic feedback allows the therapy to be corrected instantaneously.

Preventive Strategies

Molecular testing would work to help identify high-risk individuals in relation to certain diseases. In this regard, BRCA1/BRCA2 mutation carriers are able to take preventive precautions to reduce the risk of breast and ovarian cancer.

Ethical and Practical Considerations

Data Privacy and Security

The outcomes of genetic testing include colossal data and threat to confidentiality and abuse. Secrecy of patient information is a very essential ethical requirement.

Cost and Accessibility

Only low resource settings can afford targeted therapy and molecular diagnostics. The increase in the availability of such tools is a topical issue on the international level.

Interpretation of Results

Genetic variations are generally complex and cannot be easily interpreted into outcomes that can be easily understood in clinical terms. It also requires specialization and collaboration to have the expertise needed to read it in a proper way.

Equity in Healthcare

The threat is the increasing disparity when personalized medicine is provided to the privileged groups. The policy frameworks and distribution of resources ought to be established to uphold equity.

The Future of Molecular Pathology

Integration with Artificial Intelligence (AI)

The AI algorithms will be trained to learn more of the molecular data since the algorithm can recognize the pattern that a human being cannot perceive. This combination presupposes rapid and more precise diagnostics.

Expansion of Liquid Biopsies

Further important functions of non-invasive testing of the circulating tumour DNA and other biomarkers in cancer diagnosis and treatment will finally come into existence.

Single Cell Sequencing

Recent technologies can examine the expression of isolated cells and even project an even deeper understanding of tumour heterology and disease pathogenesis than ever before.

Global Collaboration

Molecular testing in healthcare has been adopted with better progressive reliability and has become a primarily standard by international consortia.

Conclusion

The practice of medicine is being redefined by molecular pathology. It offers qualitative diagnosis and diagnostic biomarkers and diagnostic treatment to the diseases by assaulting the molecular etiology of disease which is the principle of individualized medicine. It has numerous applications and transforms the sphere of oncology, the management of infectious diseases, and others.

However, there are certain problems: accessibility, ethical, and equity of healthcare provision. The subsequent advancement of the technologies and the elevated array of technologies, when coupled with AI and genomics, molecular pathology will cross the threshold of personalized medicine.

Ultimately, the goal as been set: to move towards a case-based model of treatment, whereby the treatment of various patients begins with the individual molecular profile leading to the development of the case into better health. Molecular pathology is not a means of this future, but a measure of precision and of attention in medicine.