Applications of Pyrrole and Pyridine-based Heterocycles in Cancer Diagnosis and
Treatment
Authors: Tyagi Rajdeep , Yadav Kanchan , Srivastava Nitin , Sagar Ram 
Published: December 2023

Background::
The escalation of cancer worldwide is one of the major causes of economy burden
and loss of human resources. According to the American Cancer Society, there will be 1,958,310 new cancer
cases and 609,820 projected cancer deaths in 2023 in the United States. It is projected that by 2040, the burden
of global cancer is expected to rise to 29.5 million per year, causing a death toll of 16.4 million. The hemostasis
regulation by cellular protein synthesis and their targeted degradation is required for normal cell
growth. The imbalance in hemostasis causes unbridled growth in cells and results in cancer. The DNA of cells
needs to be targeted by chemotherapeutic agents for cancer treatment, but at the same time, their efficacy and
toxicity also need to be considered for successful treatment.

Objective::
The objective of this study is to review the published work on pyrrole and pyridine, which have
been prominent in the diagnosis and possess anticancer activity, to obtain some novel lead molecules of improved
cancer therapeutic.

Methods::
A literature search was carried out using different search engines, like Sci-finder, Elsevier, ScienceDirect,
RSC etc., for small molecules based on pyrrole and pyridine helpful in diagnosis and inducing
apoptosis in cancer cells. The research findings on the application of these compounds from 2018-2023 were
reviewed on a variety of cell lines, such as breast cancer, liver cancer, epithelial cancer, etc.

Results::
In this review, the published small molecules, pyrrole and pyridine and their derivatives, which have
roles in the diagnosis and treatment of cancers, were discussed to provide some insight into the structural features
responsible for diagnosis and treatment. The analogues with the chromeno-furo-pyridine skeleton
showed the highest anticancer activity against breast cancer. The compound 5-amino-N-(1-(pyridin-4-
yl)ethylidene)-1H-pyrazole-4-carbohydrazides was highly potent against HEPG2 cancer cell. Redaporfin is
used for the treatment of cholangiocarcinoma, biliary tract cancer, cisplatin-resistant head and neck squamous
cell carcinoma, and pigmentation melanoma, and it is in clinical trials for phase II. These structural features
present a high potential for designing novel anticancer agents for diagnosis and drug development.

Conclusion::
Therefore, the N- and C-substituted pyrrole and pyridine-based novel privileged small Nheterocyclic
scaffolds are potential molecules used in the diagnosis and treatment of cancer. This review discusses
the reports on the synthesis of such molecules during 2018-2023. The review mainly discusses various
diagnostic techniques for cancer, which employ pyrrole and pyridine heterocyclic scaffolds. Furthermore, the
anticancer activity of N- and C-substituted pyrrole and pyridine-based scaffolds has been described, which
works against different cancer cell lines, such as MCF-7, A549, A2780, HepG2, MDA-MB-231, K562, HT-
29, Caco-2 cells, Hela, Huh-7, WSU-DLCL2, HCT-116, HBL-100, H23, HCC827, SKOV3, etc. This review
will help the researchers to obtain a critical insight into the structural aspects of pyrrole and pyridine-based
scaffolds useful in cancer diagnosis as well as treatment and design pathways to develop novel drugs in the
future.