Page 59 - Bio Engineering Approaches to Cancer Diagnosis and Treatment

3.3 Antibody-based microarray 57

genetic and epigenetic modifications on many glycogens are associated with malig-
nant transformations. Through the recent advancements in proteomic technologies
for cancer-cell glycemic, many tumor-associated glycoproteins and glycoproteomics
have been utilized for diagnostic, prognostic, and therapeutic purposes. Furthermore,
tumor-associated glycoantigens generate serum antibodies, which have potential
applications as biomarkers for early breast cancer detection. The detection of aber-
rant glycosylated MUC1-specific autoantibodies correlates with colorectal cancer,
which has the capability to predict cancer with 95% specificity. However, the low
sensitivity of this marker could be used in conjunction with other markers, suggest-
ing that a combination of antibody signatures may eventually enable a biomarker
panel for the early detection of breast cancer.
Acetylation also plays an important role in the regulation of numerous Onco-
proteins which are involved in tumorigenesis and cancer progression. Protein
acetylation is involved in several processes, including cancer. Lysine N-acetylation
precisely regulates the function of histone and nonhistone proteins, and especially,
histone acetyltransferases (HATs) are dysregulated because of numerous genetic
or epigenetic alterations. Normally, HATs act as tumor suppressors and facilitate
normal cell growth, cell cycle, and help control of oncogenes. However, abnormal
acetylation could activate malignant proteins and trigger tumorigenesis. Abnormal
acetylation profiles have been used as diagnostic markers for early cancer detection.
Moreover, acetylation also has potential as a prognostic biomarker to monitor cancer
treatment. Further, epigenetic therapy, employing histone deacetylase inhibitors and
acetylation modulators, has shown promising results in treating some forms of can-
cers. Some of the proteins involved in controlling N-acetylation and their targets are
aberrantly regulated during tumorigenesis, and small molecule inhibitors such KAT,
KDAC, and bromodomain are being tested as potential anti-cancer therapies to treat
relapsed or refractory cutaneous T-cell lymphoma.
In conclusion, PTMs play an extremely important role in cancer activation by
altering signaling pathways controlled by kinases. Thus, the phosphorylation of STY
influences the kinases-phosphorylation network, which also alters responses to adju-
vant therapy.
The glycosylation of membrane receptors such RTK and GPCR could also play
an important role as a biomarker for disease diagnosis and in monitoring the effec-
tiveness of neoadjuvant and adjuvant therapy [37].
By investigating of these techniques and familiarity with PTM, it is impor-
tant to discover techniques that can detect PTMs. In proteomic techniques, earlier
researches have been confined to single biomarkers, and several reports have charac-
terized a single biomarker for the prediction of early cancer diagnosis and prognosis.
However, it has been observed that single proteomic biomarkers lack the precision to
accurately detect cancer and its clinical effectiveness is very limited. Consequently,
the use of multigene expression signatures or a panel of proteomic signatures in a
tumor sample that displays a distinct expression pattern and an enhanced diagnostic
precision, are promising candidates as early-stage biomarkers.