Who is susceptible to cancers of the breast, colon, and prostate?

Obesity and breast cancer: a review of the literature

A woman's build, the risk of breast cancer and its subsequent prognosis seem to be related. In most but not all case-control and prospective cohort studies, an inverse relationship has been found between weight and breast cancer among premenopausal women. However, most large epidemiological studies have found that overweight or obese women are at increased risk of developing postmenopausal breast cancer. It is suggested that higher body mass index is associated with a more advanced stage of breast cancer at diagnosis in terms of tumour size but data on lymph node status is not so consistent. All treatment modalities for breast cancer such as surgery, radiotherapy, chemotherapy and hormonal treatment may be adversely affected by the presence of obesity. The overall and disease-free survival is worse in most but not all studies of prognosis of obese pre- and postmenopausal women with breast cancer.

Hospitalization for prostate cancer among the older men in the longitudinal study on aging, 1984-1991

BACKGROUND

Factors associated with being hospitalized with indications of prostate cancer were examined. A secondary analysis of the older men in the Longitudinal Study on Aging (LSOA) used baseline (1984) interview data and Medicare hospital claims for 1984 through 1991.

METHODS

The analytic sample consisted of 2254 men who were 70 to 95 years old (mean 75.8 years) at baseline and who were self-respondents to the LSOA. Case-identification involved primary prostate cancer (ICD9-CM code 185) and personal history of prostate cancer (ICD9-CM code V10.46) hospital discharge diagnoses. Multivariable logistic regression techniques were used.

RESULTS

There were 154 cases (6.8%) of prostate cancer, including 109 identified by active diagnostic codes only, 15 identified by personal history codes only, and 30 identified by both. No associations with age, race, or ethnicity were observed. Being hospitalized with indications of prostate cancer was more likely in the presence of a history of cancer at any site, urinary control problems, greater body mass, maximum social interaction, or living in core Standard Metropolitan Statistical Area counties. Men who regularly attended religious services, had not seen a physician for 2 years, and did not feel in control of their health were less likely to have been hospitalized with indications of prostate cancer.

CONCLUSIONS

These data suggest that the traditional associations between prostate cancer and age, race, and ethnicity do not apply to being hospitalized with indications of the disease among older men. However, body mass, history and symptoms, personal beliefs, access, and geographic practice patterns are associated with being hospitalized with indications of prostate cancer.

p53--an acrobat in tumorigenesis

The p53 tumor suppressor protein plays a central role in maintaining genomic integrity. It does so by occupying a nodal point in the DNA damage control pathway. When cells are subject to ionizing radiation or other mutagenic events, p53 mediates cell cycle arrest or programmed cell death (apoptosis). Furthermore, some evidence suggests that p53 plays a role in the recognition and repair of damaged DNA. Biochemically, p53 is a sequence-specific transcriptional stimulator and a non-specific transcriptional repressor but also engages in multiple protein-protein interactions. Conversely, disruption of the p53 response pathway strongly correlates with tumorigenesis. p53 is functionally inactivated by structural mutations, neutralization by viral products, and non-mutational cellular mechanisms in the majority of human cancers. p53-deficient mice have a highly penetrant tumor phenotype, with over 90% tumor incidence within nine months. In some cancers, direct physical evidence exists identifying the p53 gene as a target of known environmental carcinogens such as UV light and benzolalpyrene in cancers of the skin and lung. When p53 loss occurs, cells do not get repaired or eliminated but rather proceed to replicate damaged DNA, which results in more random mutations, gene amplifications, chromosomal re-arrangements, and aneuploidy. In some experimental models, loss of p53 confers resistance to anticancer therapy due to loss of apoptotic competence. The translational potential of these discoveries is beginning to be tested in novel p53-based therapies.