Molecular Aspects of Piperine in Signaling Pathways Associated with Inflammation in Head and Neck Cancer.

Piperine, an active plant alkaloid from black pepper (Piper nigrum), has several pharmacological effects, namely antioxidant, anti-inflammatory and immunomodulatory effects, which involve inhibiting molecular events associated with various stages of cancer development. The aim of this study was to investigate the molecular mechanisms of action of piperine in relation to its potential anticancer effect on head and neck cancer cells. Parameters related to neoplastic potential and cytokine, protein and gene expression were investigated in head and neck cancer cell lines (HEp-2 and SCC-25) treated with piperine. The results of the tests indicated that piperine modified morphology and inhibited viability and the formation of cell colonies. Piperine promoted genotoxicity by triggering apoptosis and cell cycle arrest in the G2/M and S phases. A decrease in cell migration was also observed, and there was decreased expression of MMP2/9 genes. Piperine also reduced the expression of inflammatory molecules (PTGS2 and PTGER4), regulated the secretion of cytokines (IFN-γ and IL-8) and modulated the expression of ERK and p38. These results suggest that piperine exerts anticancer effects on tumor cells by regulating signaling pathways associated with head and neck cancer.

Analysis of metabolic compounds and antitumorigenic effects of Albizia niopoides and Senegalia polyphylla leaves.

The objective of this study was to quantify metabolic compounds in leaves of A. niopoides and S. polyphylla and to evaluate the antitumor potential of extracts from both species in cervical tumour cells. The physiological analyses performed were quantification of starch, sucrose, phenolic compounds and proteins. An aqueous extract was prepared and added to the SiHa cell line at concentrations of 10, 100 and 1000 µg/mL at 4h, 24h, 48h and 72h. Cell morphology, proliferation and viability were analysed. The species showed a large amount of starch and phenolic compounds. Treatment with the extract of both species caused morphological changes in SiHa cells and exhibited antiproliferative effects at a concentration of 1000 µg/ml. In cell viability test, only A. niopoides showed a significant reduction. The study presented the effects of the species against a cervical cancer cell line, where A. niopoides has already shown to be a promising plant drug.

Piperine Reduces Neoplastic Progression in Cervical Cancer Cells by Downregulating the Cyclooxygenase 2 Pathway.

Cervical cancer is the fourth-most common type of cancer in the world that causes death in women. It is mainly caused by persistent infection by human papillomavirus (HPV) that triggers a chronic inflammatory process. Therefore, the use of anti-inflammatory drugs is a potential treatment option. The effects of piperine, an amino alkaloid derived from Piper nigrum, are poorly understood in cervical cancer inflammation, making it a target of research. This work aimed to investigate the antitumor effect of piperine on cervical cancer and to determine whether this effect is modulated by the cyclooxygenase 2 (PTGS2) pathway using in vitro model of cervical cancer (HeLa, SiHa, CaSki), and non-tumoral (HaCaT) cell lines. The results showed that piperine reduces in vitro parameters associated with neoplastic evolution such as proliferation, viability and migration by cell cycle arrest in the G1/G0 and G2/M phases, with subsequent induction of apoptosis. This action was modulated by downregulation of cyclooxygenase 2 (PTGS2) pathway, which in turn regulates the secretion of cytokines and the expression of mitogen-activated protein kinases (MAPKs), metalloproteinases (MMPs), and their antagonists (TIMPs). These findings indicate the phytotherapeutic potential of piperine as complementary treatment in cervical cancer.