Posted on: Thu 23-04-2020

Scientists have recorded major breakthroughs in their quest for a natural cure for bile duct, prostate, breast, cervical and pancreatic cancers.

German researchers have demonstrated the antitumor effects of bromelain found in pineapple (Ananas comosus) and papain, which is replete in pawpaw (Carica papaya) in human bile duct cancer (cholangiocarcinoma) cell lines.

 

The American researchers from Virginia State University, Petersburg, United States (U.S.) investigated the effect of papaya seeds on prostate cancer (PC) using PC-3 cell line because papaya seeds have effects on the male reproductive system notably decreasing sperm concentration, motility, and viability, leading to azoospermia after short-to-long-term treatment.

The black seeds from yellow (ripe) papaya and white seeds from green (unripe) papaya were harvested and then extracted in water, 80 per cent methanol, and hexane. The cytotoxic effects of seeds extracts were determined using a WST-1 proliferation assay. The amount of total polyphenols was determined using Folin Ciocalteu reagent.

The results showed the methanol extracts from black seeds significantly (P < 0.05) decreased cell proliferation of PC-3 cells whereas hexane- and water-extracts have no effect. However, the water-extract from white seeds stimulated PC cell proliferation. The black seeds contained significantly more polyphenols than that of white seeds. The data suggest that black seeds from papaya have anticancer effects on PCs whereas white seeds stimulated prostate cancer proliferation.

The anticancer effect of black seeds may be because of their high concentration of polyphenols.

The researchers concluded: “The black seeds from papaya may have a potential to reduce growth of prostate cells; however, consumption of white seeds should be avoided as they may stimulate pre-existing prostate cancer.”

Meanwhile, a new study indicates exercise can help prevent liver cancer. According to a study published in the Journal of Hepatology, exercise retards development of liver cancer by direct effects independent of weight control in an animal model that closely resembles humans with fatty liver disease.

Pawpaw seeds

Commisso said: “Pancreatic cancer is predicted to soon become the second-leading cause of cancer-related deaths in the U.S.

“Given that the five-year survival rate for people newly diagnosed is less than 10 per cent, it is crystal clear that we need better therapies—and finding new cancer targets can help us tailor treatments and possibly save the lives of many more patients.”

Commisso added: “This study illustrates the potential to target pH balance as an approach to combat pancreatic cancer. Our next step is to work with the Conrad Prebys Center for Chemical Genomics—the drug discovery facility at our Institute—to find ways to disable NHE7 and limit the Golgi’s ability to sequester acid. If successful, cancer cells would be unable to maintain the proper pH that they need to grow.”

Also, Manzamine A, a natural product derived from certain groups of sponges, can block the growth of cervical cancer cells, report researchers. Manzamine A targets a protein that is highly expressed in many cancers, including cervical cancer, and is the first reported inhibitor of this protein.

Sponges, the members of the phylum Porifera, are a basal Metazoa clade as a sister of the Diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells.

A sponge found in Manado Bay, Indonesia, makes a molecule called manzamine A, which stops the growth of cervical cancer cells, according to a recent publication in the Journal of Natural Products submitted by researchers at the Medical University of South Carolina (MUSC) and their collaborators. Collaborators include students and investigators at the University of South Carolina (UofSC), College of Charleston, Gadjah Mada University in Indonesia and the University of Malaya in Malaysia.

The American Cancer Society estimates that there will be 13,800 new diagnoses of cervical cancer and 4,290 deaths in 2020. Though Pap tests and Human papillomavirus (HPV) vaccination have decreased the number of cervical cancer deaths, cervical cancer remains the fourth most common cancer in women.

In the current report, manzamine A reduced expression levels of a protein known to be highly expressed in a number of cancers, including cervical cancer, and to contribute to poorer patient outcomes.

Computer modeling showed that manzamine A shares similar structures with known inhibitors of the protein, yet manzamine A is 10 times more potent in blocking the problematic proteins.

Several patents have been filed on manzamine A, and a startup company is in the works.

Next steps are to establish its clinical relevance, according to Hamann.

“The goal now is to make sure that it works in animals and then try to advance it into clinical applications and further development,” said Hamann.

While these molecules can be synthesized in the laboratory, Hamann doesn’t think that’s the best process.

“Most of the starting materials for lab-based synthesis are derived from petroleum,” he explained. “In contrast, sponges in their natural habitat can be successfully farmed, and unlike other forms of aquaculture, clean the environment.”

Therefore, production of these molecules from sponges growing in the environment would likely be the best source while providing opportunities for economic development in rural Indonesia.

However, the potential to find new therapeutic uses like this one for natural products hinges on species diversity, according to Hamann.

“The preservation of species diversity is extremely important, as is the diversity of the chemicals they produce and the opportunities for treating cancer that they offer,” explained Hamann. “If 50 years of climate change remains unchecked, projections are that we may lose one-third of the global species diversity. So with that will go opportunities like this.”

Source: Guardian 

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