Enhanced Expression of Radiation-induced Leukocyte CDKN1A mRNA in Multiple Primary Breast Cancer Patients: Potential New Marker of Cancer Susceptibility

This study was designed to discover blood biomarkers of cancer susceptibility using invasive multiple (n = 21), single primary breast cancer (n = 21), and control subjects (n = 20). Heparinized whole blood was incubated at 37 °C for 2 hours after 0–10 Gy of radiation, then cell cycle arrest marker CDKN1A and apoptosis marker BBC3 mRNA were quantified. This epidemiological study was practically feasible because radiation-induced mRNA was preserved for at least 1 day whenever blood was stored at 4 °C (r2 = 0.901). Moreover, blood could be stored frozen after radiation treatment (r2 = 0.797). Radiation-induced CDKN1A and BBC3 mRNA were dose dependent, and the degree of induction of CDKN1A was correlated with that of BBC3 (r2 = 0.679). Interestingly, multiple primary cases showed higher induction of CDKN1A mRNA than single primary and control groups, whereas BBC3 did not show such differences. The results suggested that cancer susceptibility represented by the multiple primary breast cancer cases was related to over-reaction of CDKN1A mRNA, not BBC3. The study also suggests that ex vivo gene expression analysis could potentially be used as a new tool in epidemiological studies for cancer and radiation sensitivity research

Socioeconomic Impacts on Survival Differ by Race/Ethnicity among Adolescents and Young Adults with Non-Hodgkin's Lymphoma

Shorter survival has been associated with low socioeconomic status (SES) among elderly non-Hodgkin's lymphoma (NHL) patients; however it remains unknown whether the same relationship holds for younger patients. We explored the California Cancer Registry (CCR), to investigate this relationship in adolescent and young adult (AYA) NHL patients diagnosed from 1996 to 2005. A case-only survival analysis was conducted to examine demographic and clinical variables hypothesized to be related to survival. Included in the final analysis were 3,489 incident NHL cases. In the multivariate analyses, all-cause mortality (ACM) was higher in individuals who had later stage at diagnosis (P < .05) or did not receive first-course chemotherapy (P < .05). There was also a significant gradient decrease in survival, with higher ACM at each decreasing quintile of SES (P < .001). Overall results were similar for lymphoma-specific mortality. In the race/ethnicity stratified analyses, only non-Hispanic Whites (NHWs) had a significant SES-ACM trend (P < .001). Reduced overall and lymphoma-specific survival was associated with lower SES in AYAs with NHL, although a significant trend was only observed for NHWs

A design for cancer case–control studies using only incident cases: experience with the GEM study of melanoma

BACKGROUND: The population-based case-control study is not suited to the evaluation of rare genetic (or environmental) factors. The use of a novel case-control design in which cases have second primaries and controls are cancer survivors has been proposed for this purpose. METHODS: We report results from an international study of melanoma that involved population-based ascertainment of incident cases of second or subsequent primary melanoma as the 'case' group and incident cases of first primary melanoma as the 'control' group. We evaluate the validity of the study design by comparing the results obtained for phenotypic factors that have been shown consistently to be associated with melanoma in previous conventional studies with the results from a conventional case-control study conducted in Connecticut and from literature reviews. RESULTS: All but one of the known risk factors for melanoma were shown to be significantly associated with melanoma in our study, though the individual odds ratios appear to be somewhat attenuated relative to the magnitudes typically observed in the literature. CONCLUSIONS: Patients with a second or subsequent primary cancer of a single type represent a potentially valuable and under-utilized resource for the study of cancer aetiology

Low Allele Frequency of MLH1 D132H in American Colorectal and Endometrial Cancer Patients

Hereditary nonpolyposis colon cancer is caused by mutations in DNA mismatch repair genes, predominantly MLH1 and MSH2 . Classic MLH1 mutations cause an approximately 20-fold increase in colorectal cancer susceptibility. Recently, we identified a hypomorphic allele, MLH1 D132H , which impairs, but does not completely eliminate the function of MLH1 in tumor suppression. MLH1 D132H confers an approximately fivefold increase in colorectal cancer susceptibility and was first described in a cohort of Israeli colorectal cancer patients, with an estimated allele frequency of 1.3 percent. Because MLH1 D132H has only recently been described, the ethnic distribution of this risk allele is not well understood. This study was undertaken to determine both the frequencies of this risk allele in ethnic groups outside of Israel and whether families harboring this mutation have susceptibility to extracolonic cancers in the hereditary nonpolyposis colon cancer spectrum.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41396/1/10350_2005_Article_123.pd

CDKN2A Germline Mutations in Individuals with Cutaneous Malignant Melanoma

Cyclin-dependent kinase inhibitor type 2A (CDKN2A) has been identified as a major melanoma susceptibility gene based on the presence of germline mutations in high-risk melanoma families. In this study, we sought to identify and characterize the spectrum of CDKN2A mutations affecting p16 inhibitor of cyclin-dependent kinase type 4 (INK4a) in individuals with melanoma using a population-based study design. DNA samples from 1189 individuals with incident multiple primary melanoma (MPM) and 2424 with incident single primary melanoma unselected for family history of melanoma were available for screening of CDKN2A (p16INK4a) mutations. Variants were classified for functional impact based on intragenic position, existing functional data, sequence, and structural analysis. The impact of individual mutations and functional groupings was assessed by comparing frequencies in cases of MPM versus cases with a single first primary melanoma, and by comparing the reported incidence rates in first-degree relatives. Our results show that mutations occur infrequently in these high-risk groups, and that they occur mainly in exons 1alpha and 2. Rare coding variants with putative functional impact are observed to increase substantially the risk of melanoma. With the exception of the variant in position -34 of CDKN2A of known functional consequence, the remaining rare variants in the non-coding region have no apparent impact on risk

Risk of second primary cancer in men with breast cancer

INTRODUCTION: A retrospective registry-based cohort study was conducted to examine the risk of second primary cancer following the occurrence of breast cancer in males. METHODS: Data obtained from the California Cancer Registry in the period 1988 to 2003 included 1,926 men aged 85 years and younger diagnosed with a first primary breast cancer. Person-year analysis was applied to determine the risk of second primary cancers after the occurrence of a first primary breast cancer. The effects of age, race, and time since the first breast cancer diagnosis were assessed. RESULTS: Of the 1,926 male breast cancer cases, 221 (11.5%) developed a second primary cancer. Men with first incidence of breast cancer have a significantly higher risk of second cancer (standardized incidence ratio (SIR) = 1.16, 95% confidence interval (CI) = 1.01–1.32). The risk of a second site-specific cancer is elevated for breast cancer (SIR = 52.12, 95% CI = 31.83–80.49), cutaneous melanoma (SIR = 2.98, 95% CI = 1.63–5.00) and stomach cancer (SIR = 2.11, 95% CI = 1.01–3.88). There is a general tendency towards higher risks of second malignancies among younger men compared to older men and the risk increased with the passage of time. CONCLUSION: Male breast cancer patients should be monitored carefully for the occurrence of second primary cancers, especially a second primary breast cancer

Racial/ethnic variation in EBV-positive classical Hodgkin lymphoma in California populations

Epstein-Barr virus (EBV) is detected in the tumor cells of some but not all Hodgkin lymphoma (HL) patients, and evidence indicates that EBV-positive and –negative HL are distinct entities. Racial/ethnic variation in EBV-positive HL in international comparisons suggests etiologic roles for environmental and genetic factors, but these studies used clinical series and evaluated EBV presence by differing protocols. Therefore, we evaluated EBV presence in the tumors of a large (n=1,032), racially and sociodemographically diverse series of California incident classical HL cases with uniform pathology re-review and EBV detection methods. Tumor EBV-positivity was associated with Hispanic and Asian/Pacific Islander (API) but not black race/ethnicity, irrespective of demographic and clinical factors. Complex race-specific associations were observed between EBV-positive HL and age, sex, histology, stage, neighborhood socioeconomic status (SES), and birth place. In Hispanics, EBV-positive HL was associated not only with young and older age, male sex, and mixed cellularity histology, but also with foreign birth and lower SES in females, suggesting immune function responses to correlates of early childhood experience and later environmental exposures, respectively, as well as of pregnancy. For APIs, a lack of association with birth place may reflect the higher SES of API than Hispanic immigrants. In blacks, EBV-positive HL was associated with later-stage disease, consistent with racial/ethnic variation in certain cytokine polymorphisms. The racial/ethnic variation in our findings suggests that EBV-positive HL results from an intricate interplay of early- and later-life environmental, hormonal, and genetic factors leading to depressed immune function and poorly controlled EBV infection