Treatment to curb female infertility from cancer treatments found

ANI | Updated: Sep 03, 2017 08:59 IST

<p>Washington D.C. [USA], Sept 3 (<a href="/search?query=ANI">ANI</a>): According to a new study, a team of scientists have identified a drug that may protect women from life-altering infertility that commonly follows <a href="/search?query=cancer">cancer</a> <a href="/search?query=treatment">treatment</a>s.</p><p>Women who are treated for <a href="/search?query=cancer">cancer</a> with radiation or certain chemotherapy drugs are commonly rendered sterile in most of the cases.</p><p>According to a 2006 study from <a href="/search?query=Weill Cornell Medicine">Weill Cornell Medicine</a>, nearly 40 percent of all female breast <a href="/search?query=cancer">cancer</a> survivors experience premature ovarian failure, in which they lose normal function of their ovaries and often become infertile.</p><p>The current study identified a so-called checkpoint protein (<a href="/search?query=CHK2">CHK2</a>) that becomes activated when <a href="/search?query=oocyte">oocyte</a>s are damaged by radiation.</p><p><a href="/search?query=CHK2">CHK2</a> functions in a pathway that eliminates <a href="/search?query=oocyte">oocyte</a>s with DNA damage, a natural function to protect against giving birth to offspring bearing new mutations.</p><p>When the researchers irradiated mice lacking the <a href="/search?query=CHK2">CHK2</a> gene, the <a href="/search?query=oocyte">oocyte</a>s survived, eventually repaired the DNA damage, and the mice gave birth to healthy pups.</p><p>John Schimenti, the paper's senior author. <a href="/search?query=Vera Rinaldi">Vera Rinaldi</a>, a graduate student in Schimenti's lab, said, "It turns out there were pre-existing <a href="/search?query=CHK2">CHK2</a> inhibitor drugs that were developed, ironically enough, for <a href="/search?query=cancer">cancer</a> <a href="/search?query=treatment">treatment</a>, but they turned out not to be very useful for treating <a href="/search?query=cancer">cancer</a>. By giving mice the inhibitor drug, a small molecule, it essentially mimicked the knockout of the checkpoint gene."</p><p>By inhibiting the checkpoint pathway, the <a href="/search?query=oocyte">oocyte</a>s were not killed by radiation and remained fertile, enabling birth of normal pups.</p><p>Schimenti shared, "The one major concern is that even though these irradiated <a href="/search?query=oocyte">oocyte</a>s led to the birth of healthy mouse pups, it's conceivable that they harbor mutations that will become manifested in a generation or two, because we are circumventing an evolutionarily important mechanism of genetic quality control. This needs to be investigated by genome sequencing."</p><p>When doctors recognize the need for <a href="/search?query=oocyte">oocyte</a>-damaging <a href="/search?query=cancer">cancer</a> <a href="/search?query=treatment">treatment</a>s, women may have their <a href="/search?query=oocyte">oocyte</a>s or even ovarian tissue removed and frozen, but this practice delays <a href="/search?query=treatment">treatment</a>.</p><p>Also, when women run out of <a href="/search?query=oocyte">oocyte</a>s, women's bodies naturally undergo menopause, as their hormonal systems shift.</p><p>"That is a serious dilemma and emotional issue. When you layer a <a href="/search?query=cancer">cancer</a> diagnosis on top of the prospect of having permanent life-altering effects as a result of chemotherapy, and must face the urgent decision of delaying <a href="/search?query=treatment">treatment</a> to freeze <a href="/search?query=oocyte">oocyte</a>s at the risk of one's own life," noted Schimenti.</p><p>The study sets a precedent for co-administering this or related drugs and starting <a href="/search?query=cancer">cancer</a> therapy simultaneously, though such interventions would first require lengthy human trials.</p><p>Schimenti concluded by saying, "While humans and mice have different physiologies, and there is much work to be done to determine safe and effective dosages for people, it is clear that we have the proof of principle for this approach."</p><p>The study was published in Jounral <a href="/search?query=Genetics">Genetics</a>. (<a href="/search?query=ANI">ANI</a>)</p>