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Dna ploidy, cell proliferation and genetic alterations in colorectal cancer: Correlation with clinicopathological features
Biomed & Pharmacorher
1996; 50: 41 S-420 0 Elsevier, Paris
Other solid tumors
DNA
PLOLDY, CELL PROLIFERATION IN COLOREaAL CANCER: CLINICOPATHOLOGICAL FEATURES
ALTERATIONS
AND CORRELATION
GENETIC WITH
Ciaochi F, B&i M*, Becciolioi A*, G&he’ V*! Meswini L@, Palomba A@. Mug& A’, Casini Raggi C*, Pucciani F. Cortesmi C. Clinica Chin&a Generale, ‘Laboratorio di Radiobiologia; @IstiNto di Anatomia e Istoloda Patolotica. Universitv of Florence. Up-today coloreca cancer?las been stag&l according to the criteria set out by Dukes. New systems of staina have been introduced. but none have imoroved on the high prognostic &w& of Dukes’ staging.. However! even bukes’ classifcation cannot perfectly predict outcome for a particular Individual. For this xason. interest has now surrounded the investigation of biological parameters of large bowel cancer, including DNA ploidy, cell proliferation and alterations in oncogenes and tumour suppressor genes. These biological charactefistics may reflect the aggressiveness of the Nmour and its eventual progoons Eighty-one patients, underwent radical resection of colorectal cancer, were prospectively included in the present study. The following biological parameters were assessed for each patient: 1) Nmour cell DNA content (ploidy) and cell proliferation (S phase cell fraction), as determined by flow cytometry on fresh Nmour specimens; 2) cell proliferation evaluated by [%I thymidine labelling index, 3) presence of mutations and allelic loss of the p53 hunour suppressor gene on the short 8rm of cbromosom 17; 4) expression of c-myc oncogeoe (by the dosing of respective mRNA) and 5) the presence of mutations of k-ras oncogene. These parameters were then correlated with Nmwr staging (Dukes and TNM classifications) and other clinicooatholonical variables such as aae and sex of patiems~ NmoUr lbcatiott, histologic’al grad< character of invasive &gin (pushing or mtiltradng), presence or absence of conspicas periNm0rZ.t lymph&c infiltmtionl No significant correlation has been found between bidogical parameters and histopathological features, even if DNA aneuploidy and higher S phase fractions seem to be associated with more advanced and less differentiated Nmours. Regarding tumour site, a higher frequency of aoeuploid amours has been found in left sided and rectal cancers in comparison with right sided cancers. Furthermore, allelic loss and mutations on the short arm of chromosome 17 seem to be more freq!ent in distal and rectal cancers; an overexpression of c-myc has been observed m the same locations Concerning K-ras mutations, they have been more frequent in rectal cancer when compared with distal and proximal cancers. In conclusion. our tindmrrs semn to suraest that there is a different bioloercal pattern for di&l bowel Gd rectal cance~when compared wth proximal btwel; otoreover. it is likely that prognostic information which can be collected from biological pammete& mighi be-dependent on the very site of the Nmour
EFFECT
OF
FLUVASTATIN
ON COLON
TUMOR
‘M. Del Tacca, ID. Nardw tG. Cocci. IF. Innocenti, Falcone, PG. Malvaldi, 3P.F. Conte and 4R. Danesi
CELLS 2M. Andreucceni,
sAr
‘lstituio di Farmacoloaia Medica. 2Dioartimento dl Biomedicina Sperimentale, lnfenwa e PLbbllca. Se&e di batologfa Generale. Universitti di Plsa. Via Roma 55; sUnit?i Operativa di Oncologia Medica. Ospedale S. Chiara. Via Roma 57: 4Scuola Suoeriore di Studi Universitari e di Perfezionamento S. Anna. Via Carduccj40. Plsa, Italy The interaction of small GTP-binding protems of the ras superfamily with plasma and intracellular membranes requires their post-translational modlticalion with non-&ml lipids. The mevalontc acid biosynthetic pathway generates farnesyl and geranylgeranyl isoprenoids for post-translational prenylation of r&and related proieins involved in cell signalling and ml&is. In the present study we investiaated if therapeutic strateaies could be developed which taiget protein iioprenylation in malignant cells. Cellular depletion of prenyl groups dewed from mevafonic acid was obtained by fluvastatln (Lescol, Sandaz Pharma. Easel. Switzerland). a novel synthetic inhibitor of hydroxy-methyl-glutaryl-CoA reductase. SW 480. SW620 and COLO 320DM human colon cancer cells were treated with fluvastatin 0.1-100 PM for 72 h and cell growth was measured by metabolic conversion of the ietrazolium compound XTT. A dose-dependent decrease in cell survival was observed, with reduction of viability to 50% of control at 4.5, 3.9 and 5.1 FM for SW 480, SW620 and COLO 320DM cells, respectively. Cancer cells treated with fluvastatin exhlbited promment morphological changes; these were followed by DNA damage detected as multiple of 180 base-pair fragments by agarose gel electrophoresis. In both cases mevalonic acid 100 flM proved to be very affective on reducing cylotoxicity and apoptosis induced by fluvastatin. To document whether cell damage was dependent on the inhibitoN effect of the drum on cholesterol biosynthesis, cancer cells were treaded with fluvaslatin 3-50 FM for 72 h and cholesterol was extracted with methanoL’chloroform. The enzymatic assay of the steroid showed that the total amount of cholesterol produced by cells was not reduced by treatment. indicating that both cytotoxicify and apoptosis induced by fluvastatin were not dependent on cellular depleiion of cholesterol. Finally. immunobloning analysis of the cytoskeleton-associated protein p21 rho A revealed that fluvastatln 10 PM was able to inhibit its prenylation. In conclusion, the results of the present study provide evidence that dissection of the biochemical pathway of non-sterol lsaprenoid biosynthesis and post-franslatlon protein isoprenylation reveals new avenues for drug discovery I” cancer treatment.
1996; 50: 41 S-420 0 Elsevier, Paris
Other solid tumors
DNA
PLOLDY, CELL PROLIFERATION IN COLOREaAL CANCER: CLINICOPATHOLOGICAL FEATURES
ALTERATIONS
AND CORRELATION
GENETIC WITH
Ciaochi F, B&i M*, Becciolioi A*, G&he’ V*! Meswini L@, Palomba A@. Mug& A’, Casini Raggi C*, Pucciani F. Cortesmi C. Clinica Chin&a Generale, ‘Laboratorio di Radiobiologia; @IstiNto di Anatomia e Istoloda Patolotica. Universitv of Florence. Up-today coloreca cancer?las been stag&l according to the criteria set out by Dukes. New systems of staina have been introduced. but none have imoroved on the high prognostic &w& of Dukes’ staging.. However! even bukes’ classifcation cannot perfectly predict outcome for a particular Individual. For this xason. interest has now surrounded the investigation of biological parameters of large bowel cancer, including DNA ploidy, cell proliferation and alterations in oncogenes and tumour suppressor genes. These biological charactefistics may reflect the aggressiveness of the Nmour and its eventual progoons Eighty-one patients, underwent radical resection of colorectal cancer, were prospectively included in the present study. The following biological parameters were assessed for each patient: 1) Nmour cell DNA content (ploidy) and cell proliferation (S phase cell fraction), as determined by flow cytometry on fresh Nmour specimens; 2) cell proliferation evaluated by [%I thymidine labelling index, 3) presence of mutations and allelic loss of the p53 hunour suppressor gene on the short 8rm of cbromosom 17; 4) expression of c-myc oncogeoe (by the dosing of respective mRNA) and 5) the presence of mutations of k-ras oncogene. These parameters were then correlated with Nmwr staging (Dukes and TNM classifications) and other clinicooatholonical variables such as aae and sex of patiems~ NmoUr lbcatiott, histologic’al grad< character of invasive &gin (pushing or mtiltradng), presence or absence of conspicas periNm0rZ.t lymph&c infiltmtionl No significant correlation has been found between bidogical parameters and histopathological features, even if DNA aneuploidy and higher S phase fractions seem to be associated with more advanced and less differentiated Nmours. Regarding tumour site, a higher frequency of aoeuploid amours has been found in left sided and rectal cancers in comparison with right sided cancers. Furthermore, allelic loss and mutations on the short arm of chromosome 17 seem to be more freq!ent in distal and rectal cancers; an overexpression of c-myc has been observed m the same locations Concerning K-ras mutations, they have been more frequent in rectal cancer when compared with distal and proximal cancers. In conclusion. our tindmrrs semn to suraest that there is a different bioloercal pattern for di&l bowel Gd rectal cance~when compared wth proximal btwel; otoreover. it is likely that prognostic information which can be collected from biological pammete& mighi be-dependent on the very site of the Nmour
EFFECT
OF
FLUVASTATIN
ON COLON
TUMOR
‘M. Del Tacca, ID. Nardw tG. Cocci. IF. Innocenti, Falcone, PG. Malvaldi, 3P.F. Conte and 4R. Danesi
CELLS 2M. Andreucceni,
sAr
‘lstituio di Farmacoloaia Medica. 2Dioartimento dl Biomedicina Sperimentale, lnfenwa e PLbbllca. Se&e di batologfa Generale. Universitti di Plsa. Via Roma 55; sUnit?i Operativa di Oncologia Medica. Ospedale S. Chiara. Via Roma 57: 4Scuola Suoeriore di Studi Universitari e di Perfezionamento S. Anna. Via Carduccj40. Plsa, Italy The interaction of small GTP-binding protems of the ras superfamily with plasma and intracellular membranes requires their post-translational modlticalion with non-&ml lipids. The mevalontc acid biosynthetic pathway generates farnesyl and geranylgeranyl isoprenoids for post-translational prenylation of r&and related proieins involved in cell signalling and ml&is. In the present study we investiaated if therapeutic strateaies could be developed which taiget protein iioprenylation in malignant cells. Cellular depletion of prenyl groups dewed from mevafonic acid was obtained by fluvastatln (Lescol, Sandaz Pharma. Easel. Switzerland). a novel synthetic inhibitor of hydroxy-methyl-glutaryl-CoA reductase. SW 480. SW620 and COLO 320DM human colon cancer cells were treated with fluvastatin 0.1-100 PM for 72 h and cell growth was measured by metabolic conversion of the ietrazolium compound XTT. A dose-dependent decrease in cell survival was observed, with reduction of viability to 50% of control at 4.5, 3.9 and 5.1 FM for SW 480, SW620 and COLO 320DM cells, respectively. Cancer cells treated with fluvastatin exhlbited promment morphological changes; these were followed by DNA damage detected as multiple of 180 base-pair fragments by agarose gel electrophoresis. In both cases mevalonic acid 100 flM proved to be very affective on reducing cylotoxicity and apoptosis induced by fluvastatin. To document whether cell damage was dependent on the inhibitoN effect of the drum on cholesterol biosynthesis, cancer cells were treaded with fluvaslatin 3-50 FM for 72 h and cholesterol was extracted with methanoL’chloroform. The enzymatic assay of the steroid showed that the total amount of cholesterol produced by cells was not reduced by treatment. indicating that both cytotoxicify and apoptosis induced by fluvastatin were not dependent on cellular depleiion of cholesterol. Finally. immunobloning analysis of the cytoskeleton-associated protein p21 rho A revealed that fluvastatln 10 PM was able to inhibit its prenylation. In conclusion, the results of the present study provide evidence that dissection of the biochemical pathway of non-sterol lsaprenoid biosynthesis and post-franslatlon protein isoprenylation reveals new avenues for drug discovery I” cancer treatment.