Category Archives: Transhuman News

August 17, 2017 Human chromosomes (grey) capped by telomeres (white). Credit: PD-NASA; PD-USGOV-NASA

A mutation that helps make cells immortal is critical to the development of a tumor, but new research at the University of California, Berkeley suggests that becoming immortal is a more complicated process than originally thought.

The key to immortalization is an enzyme called telomerase, which keeps chromosomes healthy in cells that divide frequently. The enzyme lengthens the caps, or telomeres, on the ends of chromosomes, which wear off during each cell division.

When the telomeres get too short, the ends stick to one another, wreaking havoc when the cell divides and in most cases killing the cell. The discovery of telomerase and its role in replenishing the caps on the ends of the chromosomes, made by Elizabeth Blackburn and Carol Greider at UC Berkeley and John Szostak at Harvard University in the 1980s, earned them a Nobel Prize in Physiology or Medicine in 2009.

Because telomeres get shorter as cells age, scientists theorized that cancer cells - which never age - become immortalized by turning on production of telomerase in cells that normally don't produce it, allowing these cells to keep their long telomeres indefinitely. An estimated 90 percent of all malignant tumors use telomerase to achieve immortality, and various proposed cancer therapies focus on turning down the production of telomerase in tumors.

The new research, which studied the immortalization process using genome-engineered cells in culture and also tracked skin cells as they progressed from a mole into a malignant melanoma, suggests that telomerase plays a more complex role in cancer.

"Our findings have implications for how to think about the earliest processes that drive cancer and telomerase as a therapeutic target. It also means that the role of telomere biology at a very early step of cancer development is vastly underappreciated," said senior author Dirk Hockemeyer, a UC Berkeley assistant professor of molecular and cell biology. "It is very likely that what we find in melanoma is true for other cancer types as well, which would warrant that people look more carefully at the role of early telomere shortening as a tumor suppressing mechanism for cancer."

The results will be reported online August 17 as a "first release" publication from the journal Science.

From nevus to cancer

Hockemeyer and his UC Berkeley colleagues, in collaboration with dermatopathologistBoris Bastian and his colleagues at UCSF, found that immortalization is a two-step process, driven initially by a mutation that turns telomerase on, but at a very low level. That mutation is in a promoter, a region upstream of the telomerase gene - referred to as TERT - that regulates how much telomerase is produced. Four years ago, researchers reported that some 70 percent of malignant melanomas have this identical mutation in the TERT promoter.

The TERT promoter mutation does not generate enough telomerase to immortalize the pre-cancerous cells, but does delay normal cellular aging, Hockemeyer said, allowing more time for additional changes that turns telomerase up. He suspects that the telomerase levels are sufficient to lengthen the shortest telomeres, but not keep them all long and healthy.

If cells fail to turn up telomerase, they also fail to immortalize, and eventually die from short telomeres because chromosomes stick together and then shatter when the cell divides. Cells with the TERT promoter mutation are more likely to up-regulate telomerase, which allows them to continue to grow despite very short telomeres.

Yet, Hockemeyer says, telomerase levels are marginal, resulting is some unprotected chromosome ends in the surviving mutant cells, which could cause mutations and further fuel tumor formation.

"Before our paper, people could have assumed that the acquisition of just this one mutation in the TERT promoter was sufficient to immortalize a cell; that any time when that happens, the telomere shortening is taken out of the equation," Hockemeyer said. "We are showing that the TERT promoter mutation is not immediately sufficient to stop telomeres from shortening."

It is still unclear, however, what causes the eventual up-regulation of telomerase that immortalizes the cell. Hockemeyer says that it's unlikely to be another mutation, but rather an epigenetic change that affects expression of the telomerase gene, or a change in the expression of a transcription factor or other regulatory proteins that binds to the promoter upstream of the telomerase gene.

"Nevertheless, we have evidence that the second step has to happen, and that the second step is initiated by or is occurring at a time where telomeres are critically short and when telomeres can be dysfunctional and drive genomic instability," he said.

In retrospect, not a surprise

Though most cancers seem to require telomerase to become immortal, only some 10 to 20 percent of cancers are known to have a single-nucleotide change in the promoter upstream of the telomerase gene. However, these include about 70 percent of all melanomas and 50 percent of all liver and bladder cancers.

Hockemeyer said that the evidence supporting the theory that the TERT promoter mutation up-regulated telomerase has always been conflicting: cancer cells tend to have chromosomes with short telomeres, yet have higher levels of telomerase, which should produce longer telomeres.

According to the new theory, the telomeres are short in precancerous cells because telomerase is turned on just enough to maintain but not lengthen the telomeres.

"Our paper reconciles contradictory information about the cancers that carry these mutations," Hockemeyer said.

The finding also resolves another recent counterintuitive finding: that people with shorter telomeres are more resistant to melanoma. The reason, he said, is that if a TERT promoter mutation arises to push a precancerous lesion - the mole or nevus - toward a melanoma, the chances are greater in someone with short telomeres that the cell will die before it up-regulates telomerase and immortalizes the cells.

The study also involved engineering TERT promoter mutations in cells differentiated from human pluripotent stem cells and following their progression toward cellular immortality. The results were identical to the progression seen in human skin lesions obtained from patients in UCSF's Helen Diller Family Comprehensive Cancer Center and examined in the Clinical Cancer Genomics Laboratory, which Bastian directs.

Explore further: Unraveling the mystery of why cancer cells survive and thrive

More information: K. Chiba el al., "Mutations in the promoter of the telomerase gene TERT contribute to tumorigenesis by a two-step mechanism," Science (2017). science.sciencemag.org/lookup/ 1126/science.aao0535

Scientists at the Max Planck Institute of Immunobiology and Epigenetics in Freiburg have gained important insights for stem cell research which are also applicable to human tumours and could lead to the development of new ...

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Two-step process leads to cell immortalization and cancer - Medical Xpress

Blogs | Aug. 17, 2017

There are time-shattering realities that take place every time a priest offers Mass.

Who has not dreamt of time travel?

My version of this came one day in an out of the way bookstore some years back.

Browsing the shelves of used books is always interesting. Often, the more shabby the emporium, the rarer the gems to be found there. Such was the case that day. I spied a book on the French Revolution - a set text at school, and taking it from the shelf, looked at the cover. It was the first time Id set eyes upon the volume in decades. A host of memories flooded back. On opening it, I noticed a name written on the inside leaf: mine.

To look at the writing of ones younger self provokes a curious cavalcade of emotions. I ran my finger over the signature.

Needless to say, I bought the book and took it home and placed it on a shelf. Unsurprisingly, I have never read it, or even glanced at the text since. I have opened it, though, just to look at the signature once more. And, every time I do, I am transported back in time to a day and year when all seemed possible. Its time travel of a sort emotionally at least.

In 1895, two events related to time travel occurred one in the realm of literary fiction, the other in the field of scientific theory. In London, the scientist-turned-novelist H.G. Wells was putting the finishing touches to what, in speculative fiction, was to become a seminal novel: The Time Machine.

At the same time, in Switzerland, oblivious of Wells soon-to-be-published work, there was a daydreaming student who was struggling to complete his education. Later, while working as a clerk, he continued to daydream. His were no ordinary daydreams, however. They were what the young man termed thought experiments and one of the subjects upon which he sat thinking was the nature of space and its relationship to time. Ten years later, to the consternation of the scientific establishment, his thought experiments crystallized into a strange new theory that seemed to turn accepted Newtonian physics on its head. The clerks name was Albert Einstein; and his theory, published in 1905, was on special relativity. It appeared to make viable - theoretically at least - the concept of time travel. Soon, his ideas came to the notice of others, with the first practical experiments in relativity taking place as early as 1919. So too began, for some at least, the challenge to build the worlds first time machine.

Of course, no such machine has yet appeared. What is deemed theoretically possible has, to date, proved elusive outside the world of fiction and the studios of Hollywood. In any event, in the 1960 film adaptation of Wells The Time Machine, we see all too clearly that the initial thrill of time travel is soon replaced by a morbid sense of where mankinds future may lie. More 1960s than 1890s, the future as depicted in that film consisted of a post-apocalyptic netherworld inhabited by a divided and joyless bunch of humans and sub-humans. To be fair, when the film was made the world did appear to be only minutes away from atomic annihilation. Perhaps the thinking then was that knowing what the future held was not such a good idea after all.

Wells was famously an atheist. It may have come as a surprise to him, therefore, to learn that Catholics take to the concept of time travel not only easily but readily. Wells hero time traveled endlessly, backward and forward, in a materialistic universe. We, however, have another set of gears; and they can take us upwards, inwards, as well as beyond. A form of this time travel, and one central to our faith, the source and summit of all we hold dear, is the Holy Mass.

By way of explanation, let me point to some interesting passages in the best place to begin any exploration of doctrinal matters: The Catechism of the Catholic Church (CCC).

The CCC states that the Holy Mass is part of a future event:

1326 by the Eucharistic celebration we already unite ourselves with the heavenly liturgy and anticipate eternal life, when God will be all in all.

The CCC goes on to say that it also brings forth a past event:

1330 The Holy Sacrifice makes present the one sacrifice of Christ the Savior.

1362 The Eucharist is the memorial of Christ's Passover, the making present and the sacramental offering of his unique sacrifice, in the liturgy of the Church which is his Body.

Returning to the beginnings of salvation history, the CCC then recalls the scriptural understanding of remembering the Passover:

1363 In the sense of Sacred Scripture the memorial is not merely the recollection of past events but the proclamation of the mighty works wrought by God for men.In the liturgical celebration of these events, they become in a certain way present and real. This is how Israel understands its liberation from Egypt: every time Passover is celebrated, the Exodus events are made present to the memory of believers so that they may conform their lives to them.

The CCC adds that this recalling of the Passover assumes its full meaning in relation to Christs sacrifice on Calvary:

1364 In the New Testament, the memorial takes on new meaning. When the Church celebrates the Eucharist, she commemorates Christ's Passover, and it is made present the sacrifice Christ offered once for all on the cross remains ever present.

In summing up this section, the CCCs conclusion is more mind-expanding than any science fiction. The Holy Mass is nothing less than a summation of time, a completion of it in Christ. Quoting St. Ignatius of Antioch, the section concludes as follows:

1405 There is no surer pledge or dearer sign of this great hope in the new heavens and new earth "in which righteousness dwells,"than the Eucharist. Every time this mystery is celebrated, "the work of our redemption is carried on" and we "break the one bread that provides the medicine of immortality, the antidote for death, and the food that makes us live forever in Jesus Christ.

Time travel has been a popular trope in storytelling in different genres except perhaps in the documentary. Nevertheless, it is precisely that genre which records the truth of the world around us. So it is one that Catholics are particularly interested in, and never more so than in regard to the truth of the time-shattering realities taking place at each Eucharist.

On a future date, when someone informs you that Holy Mass is dull, especially if it is a young person, you may wish to tell them that you have something significant to impart. Then, taking them aside, begin to speak of the reality of time travel.

The rest is here:
Time Travel for Beginners - National Catholic Register (blog)

GRAND RAPIDS, Mich. (WOTV) Im sure everyoneknows about the benefits of Aloe Vera for your skin. It is a wonderful help to minor burns, rashes, poison ivy and even benefits wound healing.But there is even more to this medicinal plant than that.

Aloe vera, taken internally is good for pretty much everyone and has been one of the most important plants used in folk medicine. The Egyptians referred to aloe as the plant of immortality.

So just like our external skin is lining of the gut, the bronchial tubes and the digestive tract can also benefit from the healing effect of aloe vera.

Taken internally, aloe vera juice aids the digestion and absorption of nutrients, helps control blood sugar, increases energy production, promotes cardiovascular health, improves liver function, and boosts the immune system.

The gel has a bitter taste that is both cooling and soothing to the body.

Try taking 1 2 tablespoons ofaloe vera gel in the morning on an empty stomach. Aloe helps clear the toxins out of the digestive system and will help you maintain young and healthy skin.

*Not for pregnant women or children under 5 years.

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Surprising benefits of aloe vera - WOTV4women.com