Can postfertile life stages evolve as an anticancer mechanism?

by Fr édéric Thomas, Mathieu Giraudeau, François Renaud, Beata Ujvari, Benjamin Roche, Pascal Pujol, Michel Raymond, Jean-François Lemaitre, Alexandra Alvergne Why a postfertile stage has evolved in females of some species has puzzled evolutionary biologists for over 50 years. We propose that existing adaptive explanations have underestimated in their formulation an important parameter operating both at the specific and the individual levels: the balance between cancer risks and cancer defenses. During their life, most multicellular organisms naturally accumulate oncogenic processes in their body. In parallel, reproduction, notably the pregnancy process in mammals, exacerbates the progression of existing tumors in females. When, for various ecologi cal or evolutionary reasons, anticancer defenses are too weak, given cancer risk, older females could not pursue their reproduction without triggering fatal metastatic cancers nor even maintain a normal reproductive physiology if the latter also promotes the growth of existing oncogenic processes, e .g., hormone-dependent malignancies. At least until stronger anticancer defenses are selected for in these species, females could achieve higher inclusive fitness by ceasing their reproduction and/or going through menopause (assuming that these traits are easier to select than anticancer defenses), thereby limiting the risk of premature death due to metastatic cancers. Because relatively few species experien...
Source: PLoS Biology: Archived Table of Contents - Category: Biology Authors: Source Type: research

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This study aimed to determine whether night shift work is a significant factor for breast cancer risk. The case–control study was conducted from 2015–2019 in the Łódź region. The case group included 494 women diagnosed with malignant breast cancer; the control group included 515 healthy women. The research tool was an anonymous questionnaire. In the case group, the percentage of women working shift work was 51.9%, whereas in the control group, it was 34.1% (OR = 2.08 (95% CI: 1.61; 2.69)). A more insightful examination of shift work showed that only night work has a significant impact on br...
Source: International Journal of Environmental Research and Public Health - Category: Environmental Health Authors: Tags: Article Source Type: research
rry State legislation in many U.S. states, including California, mandates informing women if they have dense breasts on screening mammography, meaning over half of their breast tissue is comprised of non-adipose tissue. Breast density is important to interpret screening sensitivity and is an established breast cancer risk factor. Environmental chemical exposures may play an important role in this, especially during key windows of susceptibility for breast development: in utero, during puberty, pregnancy, lactation, and the peri-menopause. There is a paucity of research, however, examining whether environmental chemical...
Source: International Journal of Environmental Research and Public Health - Category: Environmental Health Authors: Tags: Communication Source Type: research
Abstract Most of breast cancers are hormonedependent. Hormone treatment (contraception and menopause hormone treatment) has a promoter effect on preexisting lesions: the increase in risk decreases after stopping treatment. Hormonal contraception increases modestly the risk in current users but the amplitude of the risk remains low up to 40 years when this increase is more significant due of the number of breast cancer occurring at that age. Pregnancy decreases the risk if at a young age but after 25 years may increase the risk. Combined menopause hormone treatment is associated to a greater risk than estrogens alo...
Source: Presse Medicale - Category: General Medicine Authors: Tags: Presse Med Source Type: research
CONCLUSIONS: Breastfeeding represents a protective mechanism only in patients without genetic breast cancer predisposing mutations. Environmental and reproductive factors can impact the risk and the age of onset of breast cancer in patients carrying pathogenic mutations, but the mechanisms of action are not fully understood. PMID: 31424662 [PubMed - in process]
Source: Journal of B.U.ON. - Category: Cancer & Oncology Tags: J BUON Source Type: research
We examined the relationship between intrauterine dichlorodiphenyltrichloroethane (DDT) exposure (o,p’-DDT, p,p’-DDT, and p,p’-DDE) and mammographic breast density (MBD) in midlife, one of the strongest risk factors for breast cancer. We focused our analyses on o,p’-DDT exposure given our previous report of a positive association between intrauterine o,p’-DDT exposure and daughter’s breast cancer (BC) risk. Here we estimated associations of intrauterine serum DDTs with MBD in 224 daughters of women in the Child Health and Development Studies pregnancy cohort whose mothers did not develop...
Source: Reproductive Toxicology - Category: Toxicology Source Type: research
AbstractSTUDY QUESTIONAre there reasons that motivate young cancer survivors to ask for follow-up visits at an oncofertility unit?SUMMARY ANSWERCancer survivors request oncofertility follow-up visits for the management of treatment-related side effects or ovarian reserve evaluation, even if not (or not yet) wishing for a pregnancy.WHAT IS KNOWN ALREADYPersonalised oncofertility counselling before gonadotoxic therapies is considered standard of care for young women with newly diagnosed cancer. However, the long-term follow-up of these patients in an oncofertility unit is not described in the literature other than for the us...
Source: Human Reproduction - Category: Reproduction Medicine Source Type: research
CONCLUSION: ICs occurred unequally in specific provinceand relatively high-educated women in Korea. They were also diagnosed with early-stage breast cancer with a favorablerecurrence risk, and their outcome was better than those of patients with other breast cancers in breast cancer screening. PMID: 31244292 [PubMed - in process]
Source: Asian Pacific Journal of Cancer Prevention - Category: Cancer & Oncology Tags: Asian Pac J Cancer Prev Source Type: research
In conclusion, ASB6 could be a potential predictor and therapeutic target in patient with PABC. PMID: 31171715 [PubMed - as supplied by publisher]
Source: Bioscience Reports - Category: Biomedical Science Authors: Tags: Biosci Rep Source Type: research
Abstract In the United States, more than half of all women have used a vibrator, nearly one third of women have used a dildo, and more than three quarters of women who have sex with women have used a vibrator. Sexual devices can be used by patients with decreased libido, anorgasmia, conditions inhibiting vaginal penetration, partner erectile dysfunction, and motor or sensory disabilities. Basic knowledge of sexual devices can help obstetrician-gynecologists counsel patients about device safety, sharing, cleaning, disinfection, and material selection. Common sexual devices include vibrators, penetrative devices, an...
Source: Obstetrics and Gynecology - Category: OBGYN Authors: Tags: Obstet Gynecol Source Type: research
CONCLUSION: The combination of GnRH agonist and AI demonstrated promising long-term effect in young obese EC patients who wished to preserve their fertility. No weight gain side effects were observed. Further studies with a larger sample size are needed to fully evaluate this novel treatment regimen. PMID: 31074242 [PubMed - as supplied by publisher]
Source: Journal of Gynecologic Oncology - Category: OBGYN Tags: J Gynecol Oncol Source Type: research
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