Intraperitoneal topoisomerase-I inhibitors. Preliminary findings with 9-aminocamptothecin

The i.p. administration of topoisomerase I (Topo I) inhibitors has a pharmacologic advantage over intravenous application, including preservation of the biologically active lactone form. In our ongoing study, patients have received 9-amino-20(S)-camptothecin (9-AC) i.p. on days 1, 3, 5, 8, 10, and 12, repeated every 4 weeks. The daily dose has been escalated to level IV of 1.5 mg/m2 (9.0 mg/m2 per course), median of 3 cycles, range 1-4, with a reversible Grade 3 neutropenia in one patient. Responses included one CR (resolution of a pleural effusion), two patients without progressive disease (PD), two not evaluable, and two patients too early for evaluation. The area under the curve (AUC)i.p./AUCpl ratio (pharmacologic advantage) ranged from 7.6 to 16.5 on average, and, using nonlinear modeling, the pharmacologic decay data were fit to one- or two-compartmental models. Overall, a 9-AC i.p. application is well tolerated and anticipated to be an active regimen against i.p. malignancies, particularly those known to be sensitive to systemic Topo-I inhibitors.

BRCA1 germline mutations in women with uterine serous papillary carcinoma

OBJECTIVE

To determine the possible effects and incidence of BRCA1 and BRCA2 germline mutations in uterine serous papillary carcinoma.

METHODS

We screened DNA from 12 women with uterine serous papillary carcinoma for BRCA1 and BRCA2 germline mutations common in the Jewish population (BRCA1-185delAG and 5382insC, BRCA2-6174delT). In women with germline mutations, tumor DNA was screened for loss of heterozygosity at the appropriate loci.

RESULTS

Nine women were of Jewish Ashkenazi origin and three were non-Ashkenazi. Two of nine Ashkenazi women were carriers of germline mutations: one 185delAG mutation and one 5382insC mutation. Five women had histories of breast carcinoma before diagnosis of uterine serous papillary carcinoma. Family histories of seven women had at least one first-degree relative with malignant disease. Of those, four had at least one first-degree relative with breast, ovarian, or colon carcinoma. Both carriers had strong family histories of breast-ovarian carcinoma. Loss of heterozygosity analysis found loss of the wild-type BRCA1 allele in the primary uterine tumors.

CONCLUSION

BRCA1 germline mutations were observed in two of nine of the women in this series. The loss of heterozygosity in the tumor tissue of the carriers, coupled with the high frequency of family and patient histories of breast or ovarian malignancies, suggest that uterine serous papillary carcinoma might be a manifestation of familial breast-ovarian cancer.

Is uterine serous papillary carcinoma a BRCA1-related disease? Case report and review of the literature

OBJECTIVES

Type II endometrial carcinomas are estrogen-independent and have adverse histologic features and a substantially poorer prognosis. No risk factors have been identified. Interestingly, there is a striking clinical and histopathological similarity between serous papillary carcinomas of the ovary (OSPC), endometrium, and peritoneal cavity, suggesting a common oncogenic mechanism. Several common molecular alterations were found using molecular comparative analysis of OSPC and uterine serous papillary carcinoma (USPC). Germline mutations in the BRCA1 tumor suppressor gene predispose to breast and ovarian cancer but no association with sporadic endometrial cancer has been found. A family of Ashkenazi Jewish origin, in which one sister was first diagnosed with USPC and the second diagnosed with OSPC, led to the hypothesis that a BRCA mutation may contribute to USPC.

METHODS

Genomic DNA from both patients as well as two unaffected siblings was analyzed for the three mutations common in Ashkenazi Jews. Loss of heterozygosity (LOH) analysis was performed on DNA extracted from USPC tumor tissue.

RESULTS

Both affected sisters tested positive for BRCA1 5382insC germline mutation. LOH analysis confirmed the results.

CONCLUSIONS

We present a breast-ovarian cancer family including two sisters with advanced serous papillary carcinomas of endometrial and ovarian origins, carrying the same BRCA1 mutation (5382insC). LOH analysis on USPC tumor DNA showed loss of the wild-type allele, suggesting a causal relationship between the germline BRCA1 mutation and USPC. We believe a study examining BRCA1 mutations in a large cohort of women with this high-risk endometrial carcinoma is warranted. A positive finding may have implications for surveillance and prophylactic surgery in carriers of BRCA1 mutations.

High frequency of BRCA1 and BRCA2 germline mutations in Ashkenazi Jewish ovarian cancer patients, regardless of family history

To better understand the role of germline BRCA mutations in ovarian cancer in Ashkenazi Jews, we tested 29 consecutive patients admitted to our service for the three mutations common in this ethnic group. These mutations are 185delAG and 5382insC in BRCA1 and 6174delT in BRCA2. Six patients had both breast and ovarian cancer, and 23 had ovarian cancer only. In the first group, all women had germline mutations, 2 with each mutation. Of 23 ovarian cancer patients, 11 were carriers (48%): 6 of 185delAG, 2 of 5382insC, and 3 of 6174delT. Regarding family history, of 13 women with no family history, 3 (23%) were carriers. Of 10 women with any family history of breast or ovarian cancer, 8 (80%) were carriers. We discuss possible explanations for this surprisingly high carrier rate, including a high proportion of familial disease coupled with lack of adequate family history, lower penetrance than previously expected, or increasing penetrance in recent generations due to nongenetic factors. Our data suggest that genetic testing is merited in all Ashkenazi women with ovarian cancer, regardless of family history.

Founder BRCA1 and BRCA2 mutations in Ashkenazi Jews in Israel: frequency and differential penetrance in ovarian cancer and in breast-ovarian cancer families

Germ-line BRCA1 and BRCA2 mutations account for most of familial breast-ovarian cancer. In Ashkenazi Jews, there is a high population frequency (approximately 2%) of three founder mutations: BRCA1 185delAG, BRCA1 5382insC, and BRCA2 6174delT. This study examined the frequency of these mutations in a series of Ashkenazi women with ovarian cancer unselected for family history, compared with the frequency of these mutations in families ascertained on the basis of family history of at least two affected women. Penetrance was compared, both according to the method of family ascertainment (i.e., on the basis of an unselected ovarian cancer proband vs. on the basis of family history) and for the BRCA1 founder mutations compared with the BRCA2 6174delT mutation. There was a high frequency (10/22; [45%]) of germ-line mutations in Ashkenazi women with ovarian cancer, even in those with minimal or no family history (7/18 [39%]). In high-risk Ashkenazi families, a founder mutation was found in 59% (25/42). Families with any case of ovarian cancer were significantly more likely to segregate a founder mutation than were families with site-specific breast cancer. Penetrance was higher in families ascertained on the basis of family history than in families ascertained on the basis of an unselected proband, but this difference was not significant. Penetrance of BRCA1 185delAG and BRCA1 5382insC was significantly higher than penetrance of BRCA2 6174delT (hazard ratio 2.1 [95% CI 1.2-3.8]; two-tailed P = .01). Thus, the high rate of germ-line BRCA1/BRCA2 mutations in Ashkenazi women and families with ovarian cancer is coupled with penetrance that is lower than previously estimated. This has been shown specifically for the BRCA2 6174delT mutation, but, because of ascertainment bias, it also may be true for BRCA1 mutations.

Antisense inhibition of acetylcholinesterase gene expression causes transient hematopoietic alterations in vivo

Hematopoietic acetylcholinesterase (ACHE) gene expression and its implication for development were studied by in vivo administration to mice of an antisense phosphorothioate oligonucleotide targetted toward ACHE (AS-ACHE). Hematopoietic alterations were observed by differential cell counts and ACHE mRNA levels determined by quantified RNA polymerase chain reaction (RNA-PCR) and in situ hybridization analyses. In control mice, injected with phosphate-buffered saline and untreated, ACHE mRNA labeling with ACHE [35S]cRNA was about 10-fold higher on megakaryocytes (MK) compared with all other bone marrow cells and increased by 20-fold during MK development, similar to reports for MK actin mRNA. Drastic reductions occurred in the bone marrow lymphocyte and erythroid fractions 12 days following intraperitoneal injection of AS-ACHE (5 micrograms/g weight) into groups of four mice. RNA-PCR revealed over 1000-fold decreases in ACHE mRNA levels in lymph nodes and bone marrow at this time, while actin mRNA levels dropped by 10 and 100-fold in lymph nodes and bone marrow of AS-ACHE treated mice compared with controls. In view of the developmental increase in MK actin, this suggested arrest in MK development as well. By 20 days postinjection, bone marrow actin mRNA was fully restored and the sensitive in situ hybridization technique revealed that ACHE mRNA levels were also restored and reached levels only 2-3-fold lower than in controls in all bone marrow cells of AS-ACHE treated mice. Moreover, lymphocytes and erythroid cells repopulated to levels 25% above normal, and promegakaryocyte and mature MK fractions of the total MK were 3 and 2-fold higher, respectively, than in controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Taxol: initial Israeli experience with a novel anticancer agent

Taxol is a novel taxane derivative obtained from the bark of the Pacific yew, Taxus brevifolia, which has demonstrated substantial antitumor activity in early clinical trials. Intensive research efforts were necessary to overcome both supply problems and hypersensitivity reactions to the drug and thus assure its widespread use. Taxol is active in a variety of neoplasias, including advanced breast and ovarian tumors resistant to drugs such as doxorubicin and cisplatin, respectively. We report here the initial experience with taxol in these two disease entities in Israel, at three institutions within the framework of large multinational trials. These studies compared a) the use of two dose levels of taxol, and b) short, 3-h administration vs. a longer 24-h infusion of the drug. A total of 107 Israeli patients, 38 with ovarian cancer and 69 with breast cancer, were given 706 courses of taxol. Our results show that the administration of taxol at doses ranging between 135 and 175 mg/m2 is indeed feasible and that 3-h infusions are as well tolerated as longer administration. The main hematological toxicity was leukopenia, which was promptly reversible and was more pronounced both at the higher dose level and with the more prolonged infusion. Of the nonhematological side effects, the most prominent were alopecia, mild nausea and vomiting, limb paresthesias, fatigue and myalgia. Allergic reactions following routine premedication were mild and infrequent, never necessitating discontinuation of the drug. Clinically significant cardiac events did not occur. Taxol is an important addition to the anticancer chemotherapy armamentarium.