Page 10 - Bio Engineering Approaches to Cancer Diagnosis and Treatment

1.5 Immunoassay diagnosis technics in cancer 7

tumors present in patients [40]. For example, it can be seen that two patients
can display identical symptoms and imaging results of a certain cancer at the
time of diagnosis; however, at chemotherapy show drastically different outcomes.
This is because beside the genomic changes, the molecular sorting of individual
tumors is different and therefore needs different targeting chemotherapy in order
to have a positive outcome. Today we know that cancer is generally activated by
the acquisition of somatic DNA lesions. Cancer is a combination of both genetic
and epigenetic alterations which cause instability in the genome and implicated
genes, such as oncogenes, tumor suppressor genes, apoptotic genes, and DNA
repair genes [43]. Based on recent studies, tumor-associated somatic mutations or
copy number variations might be responsible for human colon cancer and there is
a poor correlation between expressed proteome, protein profile and DNA muta-
tion in genome of the disease. The sequencing of individual cancer genomes has
underscored the remarkable complexity and heterogeneity in the same cancer sub-
types and histopathological phenotypes, therefore it cannot be detected easily with
genomic technics. It is known that, alterations in somatic mutational sites of the
oncogenome are translated into contrarily regulated oncoproteome initiating the
cancer occurrence [40].
Thus, combination of proteomic and genomic technologies is required for early-
stage diagnosis. Biomarkers are required tools for cancer diagnosis and monitoring.
It is also known that the physiological status of the cell has an important role in
cancer diagnosis in patients. Thus biomarkers could be the hallmark at both diag-
nosis and treatment process. Gene mutation in gene transcription and translation,
and a variety of posttranslational protein modifications (PTMs) potentially contribute
to specific “biochemical footprints” of disease, which highlights the importance of
biomarkers in cancer diagnosis. In human genome-based detection of cancer using
advanced genomic technologies such as Next Gen Sequencing, digital PCR, circu-
lating free DNA technology, has not shown a true detection. Therefore, proteomic
methods and the proteogenomic technics are promising tools. Proteomic technics
provide a database of PTMs and Somatic variants that became a good complemen-
tary for histopathology.
Besides the proteome and genome technics, antibody-based immunosensor is
another technic that has been investigated for the detection of biomarkers in cancer
diagnosis. Imaging also in recent years with the aim of biomarker detection for tumor
diagnosis has been more in attention than before.
Reliability, sensitivity and specificity of noninvasive methods for detecting
CSCs utilizing currently available protein biomarkers and their PTMs are important
parameters.
During studies that have been conducted around cancer diagnosis, it is impor-
tant to detect genes and biomarkers which are related to cancer disease. Therefore,
nowadays there is a strong focus on high sensitive assay to detect these genes and
biomarkers and also usage of multiple approaches to increase their sensitivity and
their ability to detect more related biomarkers. Researcher has also shown that PTM
plays an important role in diagnosis and treatment of cancer. Here we demonstrate