Jump to content

Worrisome “quietâ€


Recommended Posts

Sept. 18, 2007

Courtesy American Association for Cancer Research and World Science staff

When it’s qui­et—al­most “too qui­et”—in movies, it’s of­ten a sign some­thing is about to go wrong for the good guys.

The same may be true of genes that guard against lung can­cer, re­search­ers have found. They iden­ti­fied 15 such genes, adding that these could help pre­dict can­cer: if their col­lec­tive ac­ti­vity be­comes too qui­et, it sug­gests oth­er fac­tors in the cell are sup­pres­sing them, a pos­si­ble step to­ward can­cer.

A test for these genes in nor­mal cells sam­pled via bron­chos­co­py could iden­ti­fy peo­ple at risk for lung can­cer, said James C. Wil­ley of the Un­ivers­ity of To­le­do, Ohio, the lead re­search­er.

In a study of 49 peo­ple, about half of whom had lung can­cer, Wil­ley and his col­leagues said they iden­ti­fied those pa­tients cor­rectly 96 per­cent of the time. Wil­ley cau­tioned that more, larg­er stud­ies will need to be done to see if such a test can iden­ti­fy fu­ture can­cer suf­fer­ers be­fore they be­come sick.

“Smok­ing causes about 90 per­cent of all lung can­cer cases, yet only about 10 to 15 per­cent of heavy smok­ers will de­vel­op lung can­cer,” said Wil­ley. “We are look­ing for new tech­niques that will al­low us to pick out the 10 to 15 per­cent of in­di­vid­u­als at high­est risk for lung can­cer from the enor­mous pool of cur­rent and form­er smok­ers.”

The Un­ited States alone has more than 40 mil­lion current or form­er heavy smok­ers, he added. And al­though in­creas­ingly pow­er­ful screen­ing tools are avail­a­ble to de­tect lung can­cer ear­ly, it’s very costly to screen all these peo­ple. The new test could lead to bet­ter tar­geted screen­ing, Wil­ley said.

To find which genes are ac­tive in lung can­cer, Wil­ley and his col­leagues look for lev­els of mes­sen­ger RNA tran­script­s—in­struc­tions cop­ied from DNA that di­rect cells to cre­ate spe­cif­ic pro­tein molecules.

Pre­vi­ously, the re­search­ers had found that genes that pro­tect lung cells from dam­age caused by smoke or tox­ins are poorly reg­u­lat­ed in lung can­cer pa­tients. In the new work, the team tested their the­o­ries by meas­ur­ing “tran­script abun­dance” of 15 genes that en­code pro­tec­tive an­ti­ox­i­dant and DNA re­pair pro­teins in lung air­way cells. Tran­script abun­dance is an in­di­ca­tor of gene ac­ti­vity.

The find­ings were pre­s­ented Sept. 18 at the Amer­i­can As­socia­t­ion for Can­cer Re­search’s In­terna­t­ional Con­fer­ence on Mo­lec­u­lar Di­ag­nos­tics in Can­cer Ther­a­peu­tic De­vel­op­ment, in At­lan­ta, Ga.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.