Oncosuppresor genes inactivation in human germ cell tumors.

276

Abstracts

110

CHROMOSOME

ANALYSIS

PETKOVI~

ISKRA,NAKI~

INSTITUT

FOR MOTHER

UNIVERSITY In this

study

the

with

was e s t a b l i s h e d Cytogenetic

pieces

obtained

Slides

were

giemsa

method.

diploid.

Number

neuroblastomas ditional

( I q

) and

out prior

analysis or bone

tumors

and

changes number

The

for the

t ( I, 5 ) described

results

the

of this

found.

one

is the

was

-

hyper-

Structural

in each

study

trypsin

revealed chromosomes

of

provide ad

of c h r o m o s o m e

chromosomal

patient.

cells

and

of

on tumour

structural

were

Of interest

in this

beginning

modified

i occured

involvement

These

and

hypotetraploid

of c h r o m o s o m e studied.

from

of m a l i g n a t

numerical were

to the

marrow

diagnosis

examination.

performed

giemsa

studies

with

was

in three

Precise

cytological

by c o n v e n t i o n a l

of n e u r o b l a s t o m a .

previously

and

carried

surgery

JOSIP.

OF M E D I C I N E

analysis

are presented.

of structural

evidence

genetati~n been

was

Cytogenetic

Two

FACULTY

of c y t o g e n e t i c

cytogenetic

KONJA

YUGOSLAVIA.

by h i s t o l o g i c a l

from

MLADEN,

HEALTH,

ZAGREB,

results

karyotypes,

rearrangementes

~EPULI¢

neuroblastoma

stained

abnormalities.

NEUROBLASTOMA

AND CHILD

analysis

Direct

aneuploid

MELITA,

OF ZAGREB,

children

therapy.

OF HUMAN

no.

finding

aberrations

-

i in the of i

have

not

condition.

111

THE t(2; 13) TRANSLOCATION IN RHABDOMYOSARCOMA B. Gibbons, B.D. Young, D. Rowe and J.S. Malpas ICRF Department of Medical Oncology, St Bartholomews Hospital, London, UK. We present two new cases and two previously reported cases o f alveolar r h a b d o m y o s a r c o m a with t(2;13). A fifth case with t(2;13) was classified as e m b r y o n a l on histological e x a m i n a t i o n although the patient had d i s s e m i n a t e d disease more typical of alveolar rhabdomyosarcoma. The sample of c h o i c e in all cases was metastatically infiltrated bone marrow, processed as a direct

Abstracts

2 77

or short term culture. Near diploid clones containing the t(2;13) were present in one patient karyotyped at presentation and one patient karyotyped at relapse. Near tetraploid clones were seen in four of the patients. A summarized review of these and other published cases confirms the strong association of t(2;13) with the alveolar sub-type of rhabdomyosarcoma and underlines the importance of examining the relationship of the translocation to known oncogenes. Constitutional karyotyping of 21 patients with rhabdomyosarcoma demonstrated normal karyotypes in all cases.

112 (3NCOSUPPRESOR GENES P.

Radice*,

Radice*,

M.A.

INACTIVATION Pierotti*,

S. Pilotti*, Nazionale

°Ospedale

San Gerardo,

of

Tumori,

via G. Venezian

via Solferino

the constitutional

mutations

originate

in the germ cells of the parents.

investigated Using

detecting

heterozygosity

the

from which

undergo

was

as HRAS1

lesions Gonferring they can origin.

a

genetic

contribute

of

of adult

germ cell

gene

tumor

mapped

losses

has

for

with been

to pediatric

to the somatic

development

probes recently

for at least

more

in

cancers

or,

of tumors

in

germ

An

telomeric

the hypothesis

genes

they may be transmitted

susceptibility

of

cases of

in the tumor DNA.

LOH

with

of oncosuppressor

In fact,

loss

to 11p13 and ilanking

(WT) gene

hut displayed

to we

tumors.

(RBI),

that were heterozygous

four showed allelic

tumor)

genes,

in six of ]6 informative

CAT and FSHB, Wilms'

subjects

are thought

oncosuppressor

retinoblastoma

tumor patients

of

Wilms'

these mutations

Our data are consistent

fates.

and

A similar analysis was performed

loci,

the inactivation

two different

the

not informative,

and INS.

causing

at

the putative

of the two 11p13 markers,

markers

Since

in tumor DNA was observed

of the tes[is.

case

M.T.

]ta]y

in a proportion

role in the development

RFLPs

Of the 15 testicular

additional

P. MondJni*,

Italy

('as retinoblastoma

to the inactivation

to two polymorphic

region

cloned. one

(LOH)

tumors

homologous

leading

their possible

probes

germinal

event

cancers

detectable

inherited

tile first

childhood

1, 20133 Milano,

16, 20052 Monza,

carrying be

V. De Benedetti*,

S. Crispino °, G. Della Porta*.

*Istituto

>lost

IN HUMAN GERM CELL TUMORS.

S. Lacerenza*,

that DXA

cells

may

to the offspring alternatively, the

tissue

of