Robert B. Jenkins

Chromosomal anomalies in oligodendroglial tumors are correlated with clinical features

Patients who have oligodendrogliomas (OD) that demonstrate loss of both 1p and 19q appear to have a better prognosis after they receive chemotherapy and radiotherapy compared with patients who have OD without these characteristics. It is unclear whether this improvement in outcome is due only to a better response to treatment. The authors investigated the correlation between genetic and clinical characteristics of OD in 33 patients who received chemotherapy with procarbazine, lomustine, and vincristine for recurrent disease after receiving radiotherapy.

Fish mapping of YAC clones at human chromosomal band 7q31.2: identification of YACS spanning FRA7G within the common region of LOH in breast and prostate cancer.

Loss of DNA sequences within human chromosomal band 7q31.2 is frequently observed in a number of different solid tumors including breast, prostate, and ovarian cancer. This chromosomal band also contains the common fragile site, FRA7G. Many of the common fragile sites occur within chromosomal regions that are frequently deleted during tumor formation but their precise position, relative to the chromosome breakpoints and deletions, has not been defined for the majority of the fragile sites. Because the frequency of expression of FRA7G is low, we analyzed the expression of FRA7G in a chromosome 7‐only somatic cell hybrid (hamster‐human). YAC clones defining a contig spanning 7q31.2 were then used as FISH probes against metaphase spreads prepared from the hybrid cells after aphidicolin induction. This analysis quickly revealed whether a specific YAC clone mapped proximal, distal, or actually spanned the region of decondensation/breakage of FRA7G. By using this approach, we have identified several overlapping YAC clones that clearly span FRA7G. Interestingly, these clones map precisely to the common region of LOH in breast cancer and prostate cancer. In addition, the MET oncogene is contained within the three YACs that span FRA7G. Genes Chromosomes Cancer 21:152–159, 1998.

Cytogenetic Abnormalities Associated with Endocrine Neoplasia

During the past decade, cytogenetic studies of solid human neoplasms have come of age. Although technically more difficult and often ambiguous in comparison with cytogenetic studies of leukemias and lymphomas (1) cytogenetic studies of many solid tumors have yielded valuable insights into tumor pathogenesis and prognosis. In addition, in the last decade we have seen increasing application of molecular genetic techniques to the study of cancer, which has contributed greatly to our understanding of mechanisms controlling cell growth. Specific genetic alterations responsible for the pathogenesis of a number of neoplasms have been identified.