Breast cancer recurrence risk in relation to antidepressant use after diagnosis

Repurposing autophagy regulators in brain tumors

Malignant brain tumors, such as glioblastoma multiforme (GBM) and brain metastases, continue to be an unmet medical challenge. Despite advances in cancer diagnostics and therapeutics, tumor cell colonization in the central nervous system renders most treatment options ineffective. This is primarily due to the selective permeability of the blood-brain barrier (BBB), which hinders the crossing of targeting agents into the brain. As such, repositioning medications that demonstrate anticancer effects and possess the ability to cross the BBB can be a promising option. Antidepressants, which are BBB-permeable, have been reported to exhibit cytotoxicity against tumor cells. Autophagy, specifically, has been identified as one of the common key mediators of antidepressant's antitumor effects. In this work, we provide a comprehensive overview of US Food and Drug Administration (FDA)-approved antidepressants with reported cytotoxic activities in different tumor models, where autophagy dysregulation was demonstrated to play the main part. As such, imipramine, maprotiline, fluoxetine and escitalopram were shown to induce autophagy, whereas nortriptyline, clomipramine and paroxetine were identified as autophagy inhibitors. Sertraline and desipramine, depending on the neoplastic context, were demonstrated to either induce or inhibit autophagy. Collectively, these medications were associated with favorable therapeutic outcomes in a variety of cancer cell models, including brain tumors.

Selective serotonin reuptake inhibitors associated with increased mortality risk in breast cancer patients in Northern Israel

BACKGROUND

Approximately one in six women in the USA takes antidepressants and a third use selective serotonin reuptake inhibitors (SSRIs) after breast cancer diagnosis. Recent investigation demonstrated serotonin receptor (5-HTR2B) expression in the breast and serotonin production as an indicator of poor breast cancer prognosis. This study investigates the association between SSRI use at different time intervals relative to breast cancer diagnosis on survival.

METHODS

A population-based sample of 6959 consecutive, newly diagnosed breast cancer cases in Northern Israel was included. Patients were recruited from January 2000 and followed up through March 2020. Participants completed risk factor questionnaires regarding medical, reproductive and family history, medication use and health habits. Full prescription data were available through the Israeli national Clalit medical database. Multivariate Cox proportional hazard models were used to determine survival based on time of SSRI use.

RESULTS

Use of SSRIs in the 5 years prior to breast cancer diagnosis was associated with a 66% increase in overall mortality (HRadj = 1.66; CI: 1.05-2.63). SSRI use that initiated after breast cancer diagnosis was associated with an 81% increase in mortality (HRadj = 1.81; CI: 1.58-2.06). Use of SSRIs in the 5 years post-diagnosis was associated with a dose-response increase (P < 0.001) in long-term mortality (>5 years). Heavy SSRI use (≥24 prescription fills) after diagnosis was associated with nearly doubling in mortality (HR = 1.99; CI: 1.39-2.83).

CONCLUSION

SSRI use prior to and after breast cancer diagnosis is associated with increased mortality in breast cancer patients. Additional research is needed to better understand mechanisms mediating this association.

Time to Update Evidence-Based Guideline Recommendations About Concurrent Tamoxifen and Antidepressant Use? A Systematic Review

Concerns around pharmacological interaction between tamoxifen and antidepressants have resulted in evidence-base guidelines that recommend avoidance or caution with concurrent use. It remains unclear however whether this interaction is clinically important. A systematic review of studies comparing endocrine therapy (including tamoxifen and aromatase inhibitors) alone or concurrent with antidepressants in breast cancer patients was performed. The literature search sought studies within MEDLINE, EMBASE, and the Cochrane Collaboration Library published from database inception until December 1, 2020. Outcomes of interest included recurrence, breast cancer-specific survival, overall mortality, quality of life, and treatment compliance. Studies were assessed with the Cochrane Risk of Bias tool for randomized controlled trials and the Newcastle Ottawa tool for case-control and cohort studies. From 695 citations, we included 15 studies (2 randomized controlled trials [255 patients], 10 retrospective cohort studies [75,678 patients], and 3 case-control studies [18,836 patients]). While between-study clinical and methodologic differences (including analysis of confounding variables) precluded formal meta-analysis, findings from included studies did not find consistent evidence that concurrent use of antidepressants (including paroxetine) with tamoxifen therapy has negative impacts on the outcomes of interest. In this systematic review, despite data from nearly 100,000 patients, concurrent use of tamoxifen and antidepressants showed no consistent negative effect on clinical outcomes. Given the recognized harm to patients of changing either endocrine therapy or antidepressants to avoid concurrent use, current evidence-based guidelines should be updated accordingly. More rigorously designed pharmacoepidemiologic studies are needed.

Prognostic value of depression and anxiety on breast cancer recurrence and mortality: a systematic review and meta-analysis of 282,203 patients

Depression and anxiety are common comorbidities in breast cancer patients. Whether depression and anxiety are associated with breast cancer progression or mortality is unclear. Herein, based on a systematic literature search, 17 eligible studies involving 282,203 breast cancer patients were included. The results showed that depression was associated with cancer recurrence [1.24 (1.07, 1.43)], all-cause mortality [1.30 (1.23, 1.36)], and cancer-specific mortality [1.29 (1.11, 1.49)]. However, anxiety was associated with recurrence [1.17 (1.02, 1.34)] and all-cause mortality [1.13 (1.07, 1.19)] but not with cancer-specific mortality [1.05 (0.82, 1.35)]. Comorbidity of depression and anxiety is associated with all-cause mortality [1.34 (1.24, 1.45)] and cancer-specific mortality [1.45 (1.11, 1.90)]. Subgroup analyses demonstrated that clinically diagnosed depression and anxiety, being female and of younger age (<60 years), and shorter follow-up duration (≤5 years) were related to a poorer prognosis. Our study highlights the critical role of depression/anxiety as an independent factor in predicting breast cancer recurrence and survival. Further research should focus on a favorable strategy that works best to improve outcomes among breast cancer patients with mental disorders.

Association of depression and anxiety disorder with the risk of mortality in breast cancer: A National Health Insurance Service study in Korea

PURPOSE

To examine whether depression, anxiety disorder, and their co-occurrence would increase the risk of mortality in patients with breast cancer, and whether antidepressant treatment would reduce the same.

METHODS

Data were retrieved from the database of the Korean National Health Insurance Service. Of 145,251 patients diagnosed with breast cancer between 2007 and 2014, 20,870 patients diagnosed with depression or anxiety disorder one year before breast cancer diagnosis were excluded. Thus, data of 124,381 patients were included in this study.

RESULTS

Depression and anxiety disorder were associated with an increased risk of mortality [Hazard Ratio (HR) 1.26, 95% CI 1.18-1.36; HR 1.14, 95% CI 1.08-1.22, respectively] and their co-occurrence further increased the risk (HR = 1.38, 95% CI 1.24-1.54). Antidepressant treatment was related to a reduced risk of mortality. Compared to patients without any psychiatric comorbidity with no antidepressant treatment, the mortality risk increased in patients with either psychiatric comorbidity or both, but the risk seemed to attenuate with antidepressant treatments.

CONCLUSION

The current findings suggest that psychiatric comorbidities are markers of increased mortality risk in patients with breast cancer, and antidepressant treatment may attenuate the risk. This underscores the need for screening and treating depression and anxiety disorders to improve survival in patients with breast cancer.

Adherence to antidepressant medications is associated with reduced premature mortality in patients with cancer: A nationwide cohort study

BACKGROUND

Depression and anxiety are common in cancer and antidepressants (AD) are efficacious treatment. The relationship between AD adherence and mortality in cancer is unclear. This study aimed to evaluate the association between adherence to AD and all-cause mortality in a population-based cohort of patients with cancer.

MATERIALS AND METHODS

We conducted a 4-year historical prospective cohort study including 42,075 patients with cancer who purchased AD at least once during the study period. Adherence to AD was modeled as nonadherence (<20%), poor (20-50%), moderate (50-80%), and good (>80%) adherence. We conducted multivariable survival analyses adjusted for demographic and clinical variables that may affect mortality.

RESULTS

During 1,051,489 person-years at risk follow-up, the adjusted hazard ratios (HR) for mortality were 0.89 (95% confidence interval [CI]: 0.83-0.95), 0.77 (95% CI: 0.66-0.72), and 0.80 (95% CI: 0.76-0.85) for the poor, moderate, and good adherence groups, respectively, compared to the nonadherent group. Analysis of the entire sample and a subgroup with depression, for cancer subtypes, revealed similar patterns for breast, colon, lung, and prostate cancers, but not for melanoma patients. Multivariate predictors of premature mortality included male gender (HR 1.48 [95% CI: 1.42-1.55]), current/past smoking status (HR 1.1, [95% CI: 1.04-1.15]; P < .0001), low socioeconomic status (HR 1.1, [95% CI: 1.03-1.17]; P < .0001) and more physical comorbidities.

CONCLUSIONS

The present study is the first to demonstrate that higher adherence to AD is associated with a decrease of all-cause mortality in a large nationwide cohort of cancer patients. Our data add to the pressing need to encourage adherence to AD among cancer patients.

CYP2D6-inhibiting medication use and inherited CYP2D6 variation in relation to adverse breast cancer outcomes after tamoxifen therapy

PURPOSE

Tamoxifen is widely used to reduce the risk of breast cancer (BC) recurrence and extend disease-free survival among women with estrogen-sensitive breast cancers. Tamoxifen efficacy is thought to be attributable to its active metabolite, which is formed through a reaction catalyzed by the P450 enzyme, CYP2D6. Inhibition of tamoxifen metabolism as a result of germline genetic variation and/or use of CYP2D6-inhibiting medications ("inhibitors") is hypothesized to increase the risk of adverse BC outcomes among women taking tamoxifen.

METHODS

The present cohort study of 960 women diagnosed with early-stage BC between 1993 and 1999 examined the association between concomitant use of CYP2D6 inhibitors and adjuvant tamoxifen and the risk of adverse BC outcomes (recurrence, second primary BC, BC mortality), both overall and according to CYP2D6 metabolic phenotype.

RESULTS

Six or more months of CYP2D6 inhibitor use concomitant with tamoxifen was not associated with any appreciable increase in risk of recurrence or second primary BC or BC mortality, and there was no clear evidence of variation by CYP2D6 metabolic phenotype.

CONCLUSIONS

These results are consistent with the relatively few other large, population-based studies conducted to date that have not observed an increased risk of adverse BC outcomes associated with CYP2D6 inhibition.

First-onset mental disorders after cancer diagnosis and cancer-specific mortality: a nationwide cohort study

Background

The diagnosis of cancer is strongly associated with the risk of mental disorders even in patients with no previous history of mental disorders. Accumulating data suggest that mental distress may accelerate tumor progression. We hypothesized therefore that mental disorders after a cancer diagnosis may increase the risk of cancer-specific mortality.

Patients and methods

We conducted a nationwide cohort study including 244 261 cancer patients diagnosed in Sweden during 2004-2009 and followed them through 2010. Through the Swedish Patient Register, we obtained clinical diagnoses of all mental disorders and focused on mood-, anxiety-, and substance abuse disorders (ICD10: F10-F16, F18-F19, F32-F33, F40-F41, and F43-45) that are commonly diagnosed among patients with cancer. We further classified the studied mental disorders into first-onset or recurrent mental disorders. We used Cox regression to estimate multivariable hazard ratios (HRs) with 95% confidence intervals (CIs) as a measure of the association between mental disorders after cancer diagnosis and cancer-specific mortality, adjusting for age, sex, calendar period, educational level, cancer stage, and cancer type at diagnosis.

Results

After cancer diagnosis, 11 457 patients were diagnosed with mood-, anxiety-, and substance abuse disorders; of which 7236 were first-onset mental disorders. Patients with a first-onset mental disorder were at increased risk of cancer-specific mortality (HR: 1.82, 95% CI: 1.71-1.92) while patients with a recurrent mental disorder had much lower risk elevation (HR: 1.14, 95% CI: 1.05-1.24). The increased cancer-specific mortality by first-onset mental disorders was observed for almost all cancer sites/groups and the association was stronger for localized cancers (HR: 2.00, 95% CI: 1.73-2.31) than for advanced cancers (HR: 1.49, 95% CI: 1.32-1.69).

Conclusions

Patients with a first-onset common mood-, anxiety-, or substance abuse disorder after cancer diagnosis may be at increased risk of cancer-specific death.

Treatment of Depression in Patients with Breast Cancer: A Critical Review

Aims and background

To summarize current knowledge on psychopharmacological and psychotherapeutic options for patients with breast cancer and comorbid depression, starting from the psychiatric viewpoint. Issues on diagnostic boundaries of depression and outcome measures are raised.

Methods

We completed a literature review from the last 30 years (until March 2012) using PubMed by pairing the key words: ‘breast cancer and depression treatment’ (about 1431 works, including 207 reviews), ‘breast cancer and antidepressants’ (about 305 works, including 66 reviews), and in particular ‘selective serotonin reuptake inhibitors and breast cancer’ (38 works, including 10 reviews) and ‘breast cancer and psychotherapy’ (603 works, including 84 reviews). Papers in the English language were selected, including recent reviews.

Results

There is little evidence for the superiority of any one specific intervention with pharmacological options or psychotherapy. The heterogeneity of assessment criteria, the small number of subjects collected in systematic studies, the difficulty in adopting standardized outcome measures, and the limited numbers of available drugs with a favorable side effect profile are the main limitations that emerge from the literature. No conclusive findings are available on mid-term/long-term treatment strategies, or when depression is part of a bipolar disorder.

Conclusions

Further research is necessary to define the most appropriate approach to depression when it occurs in comorbidity with breast cancer. A more accurate definition of the clinical phenotypes of depression in the special population of patients with breast cancer is suggested as a key issue.

Selective serotonin reuptake inhibitor use and breast cancer survival: a population-based cohort study

BACKGROUND

Nearly 50% of breast cancer patients suffer from depression or anxiety. Selective serotonin reuptake inhibitors (SSRIs), the first-line pharmacological treatment for depression, have been implicated in breast cancer development through increased prolactin levels and tamoxifen metabolism inhibition. Previous studies of breast cancer progression have focused on tamoxifen users, or have been limited by their small sample size and methodology. Therefore, we used UK population-based data to more robustly investigate the association between SSRI use and cancer-specific mortality.

METHODS

A cohort of patients with newly-diagnosed breast cancer between 1998 and 2012 was selected from English cancer registries and linked to prescription records from the Clinical Practice Research Datalink, and to death records from the Office for National Statistics. We used Cox regression models to calculate hazard ratios (HRs) comparing mortality between post-diagnostic SSRI users and non-users (using time-dependant covariates), after adjusting for demographics, comorbidities and pre-diagnosis use of hormone replacement therapy or oral contraceptives. We conducted several additional analyses to assess causality.

RESULTS

Our cohort included 23,669 breast cancer patients, of which 2672 used SSRIs and 3053 died due to their breast cancer during follow-up. After adjustment, SSRI users had higher breast cancer-specific mortality than non-users (HR = 1.27; 95% confidence interval (CI) 1.16, 1.40). However, this association was attenuated when restricting to patients with a prior history of depression (HR = 1.14; 95% CI 0.98, 1.33), and when comparing to users of other antidepressant medications (HR = 1.06; 95% CI 0.93, 1.20). There was some evidence of higher mortality among long-term SSRI users, even when restricting to patients with prior depression (HR = 1.54; 95% CI 1.03, 2.29).

CONCLUSIONS

In this large breast cancer cohort, SSRI use was associated with a 27% increase in breast cancer mortality. The cause of this is unknown; however, confounding by indication seems likely as it was largely attenuated when restricting to patients with prior depression, or when comparing SSRIs to other antidepressant medications. Clinicians should not be unduly concerned when prescribing SSRIs to breast cancer patients, but the increase in mortality among long-term SSRI users warrants further investigation.

Evidence for Detection Bias by Medication Use in a Cohort Study of Breast Cancer Survivors

In previous studies, we found modestly decreased and increased risks of second breast cancer events with the use of statins and antibiotics, respectively, after adjustment for surveillance mammography. We evaluated detection bias by comparing receipt of surveillance mammography among users of these 2 disparate classes of medication. Adult women diagnosed with early-stage breast cancer during 1990-2008 (n = 3,965) while enrolled in an integrated health-care plan (Group Health Cooperative; Washington State) were followed for up to 10 years in the Commonly Used Medications and Breast Cancer Outcomes (COMBO) Study. Categories of antibiotic use included infrequent (1-3 dispensings/12 months) and frequent (≥4 dispensings/12 months) use, and categories of statin use included less adherent (1 dispensing/6 months) and adherent (≥2 dispensings/6 months). We examined associations between medication use and surveillance mammography using multivariable generalized estimating equations and evaluated the impact of adjusting for surveillance within Cox proportional hazard models. Frequent antibiotic users were less likely to receive surveillance mammography (odds ratio (OR) = 0.90, 95% confidence interval (CI): 0.82, 0.99) than were nonusers; no association was found among infrequent users (OR = 0.96, 95% CI: 0.90, 1.03). Adherent statin use was associated with more surveillance compared with nonuse (OR = 1.11, 95% CI: 1.01, 1.25), but less adherent statin use was not (OR = 1.03, 95% CI: 0.81, 1.31). No difference in associations between medications of interest and second breast cancer events was observed when surveillance was removed from otherwise adjusted models. The influence of detection bias by medication use warrants further exploration.

Application of Mice Humanized for CYP2D6 to the Study of Tamoxifen Metabolism and Drug-Drug Interaction with Antidepressants

Tamoxifen is an estrogen receptor antagonist used in the treatment of breast cancer. It is a prodrug that is converted by several cytochrome P450 enzymes to a primary metabolite, N-desmethyltamoxifen (NDT), which is then further modified by CYP2D6 to a pharmacologically potent secondary metabolite, 4-hydroxy-N-desmethyltamoxifen (endoxifen). Antidepressants (ADs), which are often coprescribed to patients receiving tamoxifen, are also metabolized by CYP2D6 and evidence suggests that a drug-drug interaction between these agents adversely affects the outcome of tamoxifen therapy by inhibiting endoxifen formation. We evaluated this potentially important drug-drug interaction in vivo in mice humanized for CYP2D6 (hCYP2D6). The rate of conversion of NDT to endoxifen by hCYP2D6 mouse liver microsomes (MLMs) in vitro was similar to that of the most active members of a panel of 13 individual human liver microsomes. Coincubation with quinidine, a CYP2D6 inhibitor, ablated endoxifen generation by hCYP2D6 MLMs. The NDT-hydroxylation activity of wild-type MLMs was 7.4 times higher than that of hCYP2D6, whereas MLMs from Cyp2d knockout animals were inactive. Hydroxylation of NDT correlated with that of bufuralol, a CYP2D6 probe substrate, in the human liver microsome panel. In vitro, ADs of the selective serotonin reuptake inhibitor class were, by an order of magnitude, more potent inhibitors of NDT hydroxylation by hCYP2D6 MLMs than were compounds of the tricyclic class. At a clinically relevant dose, paroxetine pretreatment inhibited the generation of endoxifen from NDT in hCYP2D6 mice in vivo. These data demonstrate the potential of ADs to affect endoxifen generation and, thereby, the outcome of tamoxifen therapy.

Effect of selective serotonin reuptake inhibitors use on endocrine therapy adherence and breast cancer mortality: a population-based study

The purpose of the study was to investigate whether the concomitant use of selective serotonin reuptake inhibitors (SSRI) with tamoxifen influences the risk of death due to breast cancer, and we also investigated the association between SSRI use and adherence to oral endocrine therapy (ET). We analyzed data from BCBaSe Sweden, which is a database created by the data linkage of Registries from three different regions of Sweden. To investigate the association between ET adherence and SSRI use, we included all women who were diagnosed with non-distant metastatic ER-positive invasive breast cancer from July 2007 to July 2011 and had at least one dispensed prescription of oral tamoxifen or aromatase inhibitor. To investigate the role of concurrent administration of SSRI and tamoxifen on breast cancer prognosis, we performed a nested case–control study. In the adherence cohort, 9104 women were included in the analyses. Women who received SSRI, either before or after breast cancer diagnosis, were at higher risk for low adherence to ET. However, when the overlapping period between SSRI use and ET was >50 %, no excess risk for low adherence was observed. Non-adherence (<80 %) to ET was significantly associated with worse breast cancer survival (OR 4.07; 95 % CI 3.27–5.06). In the case–control study, 445 cases and 11125 controls were included. The concomitant administration of SSRI and tamoxifen did not influence breast cancer survival, neither in short-term (OR 1.41; 95 % CI 0.74–2.68) nor in long-term SSRI users (OR 0.85; 95 % CI 0.35–2.08). Concomitant SSRI and tamoxifen use does not seem to increase risk for death due to breast cancer. Given the positive association between continuing antidepressive pharmacotherapy for a longer period of time and adherence to ET, it is essential to capture and treat depression in breast cancer patients to secure adherence to ET.

Tamoxifen and Antidepressant Drug Interaction in a Cohort of 16,887 Breast Cancer Survivors

BACKGROUND

Controversy persists about whether certain antidepressants reduce tamoxifen's effectiveness on lowering breast cancer recurrence. We investigated whether taking tamoxifen and antidepressants (in particular, paroxetine) concomitantly is associated with an increased risk of recurrence or contralateral breast cancer.

METHODS

We examined 16 887 breast cancer survivors (TNM stages 0-II) diagnosed between 1996 and 2007 and treated with tamoxifen in two California health plans. Women were followed-up through December 31, 2009, for subsequent breast cancer. The main exposure was the percent of days of overlap when both tamoxifen and an antidepressant (paroxetine, fluoxetine, other selective serotonin reuptake inhibitors, tricyclics, and other classes) were used. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression models with time-varying medication variables.

RESULTS

Of the 16 887 women, half (n = 8099) used antidepressants and 2946 women developed subsequent breast cancer during the 14-year study period. We did not find a statistically significant increased risk of subsequent breast cancer in women who concurrently used paroxetine and tamoxifen. For 25%, 50%, and 75% increases in percent overlap days between paroxetine and tamoxifen, hazard ratios were 1.06 (95% CI = 0.98 to 1.14, P = .09), 1.13 (95% CI = 0.98 to 1.30, P = .09), and 1.20 (95% CI = 0.97 to 1.49, P = .09), respectively, in the first year of tamoxifen treatment but were not statistically significant. Hazard ratios decreased to 0.94 (95% CI = 0.81 to 1.10, P = .46), 0.89 (95% CI = 0.66 to 1.20, P = .46), and 0.85 (95% CI = 0.54 to 1.32, P = .46) by the fifth year (all non-statistically significantly). Absolute subsequent breast cancer rates were similar among women who used paroxetine concomitantly with tamoxifen vs tamoxifen-only users. For the other antidepressants, we again found no such associations.

CONCLUSIONS

Using the comprehensive electronic health records of insured patients, we did not observe an increased risk of subsequent breast cancer in women who concurrently used tamoxifen and antidepressants, including paroxetine.

Breast cancer recurrence in relation to antidepressant use

PURPOSE

Women with breast cancer frequently use antidepressants; however, questions about the effect of these medications on breast cancer recurrence remain.

METHODS

We identified 4,216 women ≥18 years with an incident stage I or II breast cancer diagnosed between 1990 and 2008 in a mixed-model healthcare delivery system linked to a cancer registry. Recurrences were ascertained from chart review. Medication exposures were extracted from electronic pharmacy records. We used multivariable Cox proportional hazards models to estimate hazard ratios (HR) and 95 % confidence intervals (CI) to assess the association between antidepressant use and breast cancer recurrence and mortality. We also conducted analyses restricted to tamoxifen users.

RESULTS

Antidepressants overall, tricyclic antidepressants, and selective serotonin reuptake inhibitors were not associated with risk of breast cancer recurrence or mortality. Women taking paroxetine only (adjusted HR: 1.66; 95 % CI 1.02, 2.71) and trazodone only (adjusted HR: 1.76; 95 % CI 1.06, 2.92), but not fluoxetine only (adjusted HR: 0.92; 95 % CI 0.55, 1.53), had higher recurrence risks than antidepressant nonusers. There was some suggestion of an increased recurrence risk with concurrent paroxetine and tamoxifen use compared with users of tamoxifen only (adjusted HR: 1.49; 95 % CI 0.79, 2.83).

CONCLUSIONS

In general, antidepressants did not appear increase risk of breast cancer recurrence, though there were some suggested increases in risk that warrant further investigation in other datasets. Our results combined systematically and quantitatively with results from other studies may be useful for patients and providers making decisions about antidepressant use after breast cancer diagnosis.

Assessing the Risks Associated with Antidepressant Use in Plastic Surgery: A Systematic Review

BACKGROUND

Antidepressant use has increased dramatically over the past decade. Although there is no question about the benefits of these medications, uncertainty exists with regard to the implications of antidepressant treatment surrounding plastic surgery. This systematic review collates all of the available literature that evaluates the risks of patient antidepressant treatment, in relation to plastic surgery.

METHODS

A comprehensive literature review of the PubMed and Cochrane databases was conducted. Articles were assessed by two independent reviewers using predefined data fields and selected using specific inclusion criteria. The two authors independently reviewed the literature and extracted data from included reviews, and discrepancies were resolved by consensus.

RESULTS

Twenty-six articles were included in the analysis and were categorized into five groups for comparison: risk of bleeding, risk of breast cancer, risk of breast cancer recurrence, breast enlargement, and miscellaneous (unique complications). Extracted information included study type, statistical analyses, conclusion, and limitations.

CONCLUSIONS

This review does not support the cessation of antidepressants in patients before plastic surgery, as the numbers needed to harm are low and the implications of withdrawal may prove to be detrimental to postoperative management. However, the use of antidepressants for mental disorders may also implicate key patient risk factors for surgical complications, and sufficient exploration into the patient's indications for the prescription is crucial. Evidence so far does not suggest that antidepressants increase the risk of breast cancer or recurrence in general, but caution should be exercised for those specifically on concurrent tamoxifen and paroxetine treatment.

Using natural language processing to improve efficiency of manual chart abstraction in research: the case of breast cancer recurrence

The increasing availability of electronic health records (EHRs) creates opportunities for automated extraction of information from clinical text. We hypothesized that natural language processing (NLP) could substantially reduce the burden of manual abstraction in studies examining outcomes, like cancer recurrence, that are documented in unstructured clinical text, such as progress notes, radiology reports, and pathology reports. We developed an NLP-based system using open-source software to process electronic clinical notes from 1995 to 2012 for women with early-stage incident breast cancers to identify whether and when recurrences were diagnosed. We developed and evaluated the system using clinical notes from 1,472 patients receiving EHR-documented care in an integrated health care system in the Pacific Northwest. A separate study provided the patient-level reference standard for recurrence status and date. The NLP-based system correctly identified 92% of recurrences and estimated diagnosis dates within 30 days for 88% of these. Specificity was 96%. The NLP-based system overlooked 5 of 65 recurrences, 4 because electronic documents were unavailable. The NLP-based system identified 5 other recurrences incorrectly classified as nonrecurrent in the reference standard. If used in similar cohorts, NLP could reduce by 90% the number of EHR charts abstracted to identify confirmed breast cancer recurrence cases at a rate comparable to traditional abstraction.

Factors associated with long-term adherence to annual surveillance mammography among breast cancer survivors

Clinical practice guidelines recommend yearly surveillance mammography for breast cancer survivors, yet many women do not receive this service. The objective of this study was to evaluate factors related to long-term surveillance mammography adherence among breast cancer survivors. We conducted a retrospective cohort study among women ≥ 18 years, diagnosed with incident stage I or II breast cancer between 1990 and 2008. We used medical record and administrative health plan data to ascertain covariates and receipt of surveillance mammography for up to 10 years after completing breast cancer treatment. Surveillance included post-diagnosis screening exams among asymptomatic women. We used multivariable repeated measures generalized estimating equation regression models to estimate odds ratios and robust 95 % confidence intervals to examine factors related to the annual receipt of surveillance mammography. The analysis included 3,965 women followed for a median of six surveillance years; 79 % received surveillance mammograms in year 1 but decreased to 63 % in year 10. In multivariable analyses, women, who were < 40 years or 80+ years of age (compared to 50-59 years), current smokers, had greater comorbidity, were diagnosed more recently, had stage II cancer, or were treated with mastectomy or breast conserving surgery without radiation, were less likely than other women to receive surveillance mammography. Women with outpatient visits during the year to primary care providers, oncologists, or both were more likely to undergo surveillance. In this large cohort study of women diagnosed with early-stage invasive breast cancer, we found that important subgroups of women are at high risk for non-adherence to surveillance recommendations, even among younger breast cancer survivors. Efforts should be undertaken to actively engage breast cancer survivors in managing long-term surveillance care.

How often did Belgian physicians co-prescribe tamoxifen with strong CYP2D6 inhibitors over the last 6 years?

AIMS

Tamoxifen is widely used in the treatment of breast cancer. It is a pro-drug metabolized to the more active endoxifen through CYP2D6. Concomitant intake of CYP2D6 inhibitors results in lower endoxifen levels and could influence efficacy. The objective of this study was to evaluate the evolution of co-prescription of tamoxifen and CYP2D6 inhibitors in Belgium.

METHODS

Data were retrieved from the Pharmanet database of the National Institute for Health and Disability Insurance for the period January 2006-December 2009. For the analysis of the evolution of the co-prescription, the period was divided in subperiods of 2 months. The category tamoxifen+CYP2D6 inhibitor was defined as women who were delivered tamoxifen and a CYP2D6 inhibitor in that subperiod. The results were validated on the period December 2011-May 2012.

RESULTS

The percentage of co-prescription decreased over time for the strong CYP2D6 inhibitors and increased for the weak CYP2D6 inhibitor, with these trends persisting in 2012. Tamoxifen and CYP2D6 inhibitors were mostly prescribed by general practitioners and gynaecologists and by general practitioners and psychiatrists, respectively.

DISCUSSION

This study shows that a proportion of women taking tamoxifen in Belgium are prescribed a strong CYP2D6 inhibitor, which could affect tamoxifen efficacy. Over time, the concomitant intake decreased. Paroxetine was the most prescribed strong CYP2D6 inhibitor. Venlafaxine, a weak CYP2D6 inhibitor, was prescribed more often. This study also shows that tamoxifen and the CYP2D6 inhibitors are not only prescribed by physicians specialized in breast cancer; therefore, all physicians should be aware of this interaction.

Metabolism and transport of tamoxifen in relation to its effectiveness: new perspectives on an ongoing controversy

Tamoxifen reduces the rate of breast cancer recurrence by approximately a half. Tamoxifen is metabolized to more active metabolites by enzymes encoded by polymorphic genes, including cytochrome P450 2D6 (CYP2D6). Tamoxifen is a substrate for ATP-binding cassette transporter proteins. We review tamoxifen's clinical pharmacology and use meta-analyses to evaluate the clinical epidemiology studies conducted to date on the association between CYP2D6 inhibition and tamoxifen effectiveness. Our findings indicate that the effect of both drug-induced and/or gene-induced inhibition of CYP2D6 activity is likely to be null or small, or at most moderate in subjects carrying two reduced function alleles. Future research should examine the effect of polymorphisms in genes encoding enzymes in tamoxifen's complete metabolic pathway, should comprehensively evaluate other biomarkers that affect tamoxifen effectiveness, such as the transport enzymes, and focus on subgroups of patients, such as premenopausal breast cancer patients, for whom tamoxifen is the only guideline endocrine therapy.

Threats to validity of nonrandomized studies of postdiagnosis exposures on cancer recurrence and survival

Studies of the effects of exposures after cancer diagnosis on cancer recurrence and survival can provide important information to the growing group of cancer survivors. Observational studies that address this issue generally fall into one of two categories: 1) those using health plan automated data that contain "continuous" information on exposures, such as studies that use pharmacy records; and 2) survey or interview studies that collect information directly from patients once or periodically postdiagnosis. Reverse causation, confounding, selection bias, and information bias are common in observational studies of cancer outcomes in relation to exposures after cancer diagnosis. We describe these biases, focusing on sources of bias specific to these types of studies, and we discuss approaches for reducing them. Attention to known challenges in epidemiologic research is critical for the validity of studies of postdiagnosis exposures and cancer outcomes.

Antidepressants: influence on cancer and immunity?

Two decades ago, it was hypothesized that antidepressants could alter the course of neoplastic diseases. However, contradictory findings indicated that antidepressants could either have carcinogenic properties or improve the disease outcome. Intriguingly, controversial results were reported on the action of antidepressant drugs on immune function. Further hypotheses proposed that antidepressants could indirectly affect the cancer prognosis through the modulation of antitumor activity. Here we review the literature in order to elucidate the influence of antidepressants on cancer and immunity.

Clinically relevant drug interactions in anxiety disorders

OBJECTIVE

Certain drugs used in the treatment of patients with anxiety disorders can interact with other psychotropic drugs and with pharmacological treatments for physical illnesses. There is a need for an updated comparative review of clinically relevant drug interactions in this area.

DESIGN

Relevant literature on drug interactions with medications used in the treatment of anxiety disorders was identified through a search in MEDLINE and EMBASE.

RESULTS

Drug interactions involving medications used to treat anxiety disorders may be pharmacokinetic, such as enzyme inhibition or induction in the cytochrome P450 system and transporter-mediated drug interactions, or pharmacodynamic, such as additive effects in causing drowsiness or additive effects at neurotransmitter receptors. Certain selective serotonin reuptake inhibitors (fluoxetine, fluvoxamine, and paroxetine) are particularly liable to be potentially involved in untoward pharmacokinetic interactions.

CONCLUSIONS

The potential for drug interactions with medications used in anxiety disorders should be the cause of clinical concern, particularly in elderly individuals. However, the liability for harmful drug interactions may be anticipated, and the risk reduced. Although not all interactions are clinically relevant, careful monitoring of clinical response and possible interactions is essential.

Administrative data algorithms to identify second breast cancer events following early-stage invasive breast cancer

BACKGROUND

Studies of breast cancer outcomes rely on the identification of second breast cancer events (recurrences and second breast primary tumors). Cancer registries often do not capture recurrences, and chart abstraction can be infeasible or expensive. An alternative is using administrative health-care data to identify second breast cancer events; however, these algorithms must be validated against a gold standard.

METHODS

We developed algorithms using data from 3152 women in an integrated health-care system who were diagnosed with stage I or II breast cancer in 1993-2006. Medical record review served as the gold standard for second breast cancer events. Administrative data used in algorithm development included procedures, diagnoses, prescription fills, and cancer registry records. We randomly divided the cohort into training and testing samples and used a classification and regression tree analysis to build algorithms for classifying women as having or not having a second breast cancer event. We created several algorithms for researchers to use based on the relative importance of sensitivity, specificity, and positive predictive value (PPV) in future studies.

RESULTS

The algorithm with high specificity and PPV had 89% sensitivity (95% confidence interval [CI] = 84% to 92%), 99% specificity (95% CI = 98% to 99%), and 90% PPV (95% CI = 86% to 94%); the high-sensitivity algorithm had 96% sensitivity (95% CI = 93% to 98%), 95% specificity (95% CI = 94% to 96%), and 74% PPV (95% CI = 68% to 78%).

CONCLUSIONS

Algorithms based on administrative data can identify second breast cancer events with high sensitivity, specificity, and PPV. The algorithms presented here promote efficient outcomes research, allowing researchers to prioritize sensitivity, specificity, or PPV in identifying second breast cancer events.

The influence of travel time on breast cancer characteristics, receipt of primary therapy, and surveillance mammography

Travel time has been shown to influence some aspects of cancer characteristics at diagnosis and care for women with breast cancer, but important gaps remain in our understanding of its impact. We examined the influence of travel time to the nearest radiology facility on breast cancer characteristics, treatment, and surveillance for women with early-stage invasive breast cancer. We included 1,012 women with invasive breast cancer (stages I and II) who had access to care within an integrated health care delivery system in western Washington State. The travel times to the nearest radiology facility were calculated for all the U.S. Census blocks within the study area and assigned to women based on residence at diagnosis. We collected cancer characteristics, primary and adjuvant therapies, and surveillance mammography for at least 2.5 years post diagnosis and used multivariable analyses to test the associations of travel time. The majority of women (68.6%) lived within 20 min of the nearest radiology facility, had stage I disease (72.7%), received breast conserving therapy (68.7%), and had annual surveillance mammography the first 2 years after treatment (73.7%). The travel time was not significantly associated with the stage or surveillance mammography after adjusting for covariates. Primary therapy was significantly related to travel time, with greater travel time (>30 min vs. ≤ 10 min) associated with a higher likelihood of mastectomy compared to breast conserving surgery (RR = 1.53; 95% CI, 1.16-2.01). The travel time was not associated with the stage at diagnosis or surveillance mammography receipt. The travel time does seem to influence the type of primary therapy among women with breast cancer, suggesting that women may prefer low frequency services, such as mastectomy, if geographic access to a radiology facility is limited.

Clinical epidemiology and pharmacology of CYP2D6 inhibition related to breast cancer outcomes

Adjuvant tamoxifen therapy of breast cancer patients with estrogen receptor-positive tumors reduces the rate of breast cancer recurrence by approximately a half. Tamoxifen is metabolized by several polymorphic enzymes, including cytochrome P450 2D6 (CYP2D6), to more active metabolites. We have reviewed the clinical pharmacology of tamoxifen and evaluated the evidence from clinical epidemiology studies regarding the association between CYP2D6 inhibition and tamoxifen effectiveness. We conclude that the impact of CYP2D6 inhibition on tamoxifen effectiveness is likely to be null or small, at least in the populations studied so far. Understanding the effect of variations in tamoxifen metabolism on breast cancer outcomes, if any, will likely require a broader perspective, including examination of the complete metabolic pathway and subgroups of patients with other markers of potentially poor tamoxifen response.

CYP2D6 inhibition and breast cancer recurrence in a population-based study in Denmark

BACKGROUND

Cytochrome P450 2D6 (CYP2D6) inhibition reduces the concentration of 4-hydroxylated tamoxifen metabolites, but the clinical relevance remains uncertain.

METHODS

We conducted a large case-control study nested in the population of 11 251 women aged 35-69 years at diagnosis of stage I-III breast cancer between 1985 and 2001 on Denmark's Jutland Peninsula and registered with the Danish Breast Cancer Cooperative Group. We identified 541 recurrent or contralateral breast cancers among women with estrogen receptor-positive (ER+) disease treated with tamoxifen for at least 1 year and 300 cancers in women with ER-negative (ER-) disease never treated with tamoxifen. We matched one control subject per case patient on ER status, menopausal status, stage, calendar time, and county, genotyped the CYP2D6*4 allele to assess genetic inhibition, and ascertained prescription history to assess drug-drug inhibition. We estimated the odds ratio (OR), associating CYP2D6 inhibition with breast cancer recurrence and adjusted for potential confounding with logistic regression. To address bias from incomplete information on CYP2D6 function, we used Monte Carlo simulation to complete a record-level probabilistic bias analysis. All statistical tests were two-sided.

RESULTS

The frequency of the CYP2D6*4 minor allele was 24% in case patients with ER+ tumors, 23% in case patients with ER- tumors, and 22% each in control subjects with ER+ and ER- tumors. In women with ER+ tumors, the associations of one functional allele with recurrence (OR = 0.99; 95% confidence interval = 0.76 to 1.3) and no functional allele with recurrence (OR = 1.4; 95% confidence interval = 0.84 to 2.3) were near null, as were those for women with ER- tumors. The near-null associations persisted when evaluated by intake of medications, by combining genotype with medication history, in the probabilistic bias analysis, or by restricting the analysis to women with ER expression confirmed by re-assay.

CONCLUSION

The association between CYP2D6 inhibition and recurrence in tamoxifen-treated patients is likely null or small.

Use of antidepressants and NSAIDs in relation to mortality in long-term breast cancer survivors

PURPOSE

The aim of this study was to assess the post-diagnosis use of antidepressants and non-steroidal anti-inflammatory drugs (NSAIDs) in relation to all-cause, breast cancer, and cardiovascular disease (CVD) mortality among long-term breast cancer survivors.

METHODS

A cohort of 3058 breast cancer survivors, who previously participated in a series of case-control studies diagnosed between 1988 and 1999 in Wisconsin. Cancer survivors completed a self-administered mailed follow-up questionnaire in 1998-2001 that addressed use of medications post-diagnosis, including antidepressants and NSAIDs. Vital status information was obtained through the National Death Index through 31 December 2006. We used multivariable Cox proportional hazards modeling to estimate hazard ratios and 95% confidence intervals (CI).

RESULTS

We identified 463 deaths due to all-causes, 163 due to breast cancer, and 93 due to CVD during follow-up. Among women who had used any antidepressant after a breast cancer diagnosis, there was an increased risk of all-cause (adjusted HR=1.50, 95%CI: 1.12-2.02) and CVD mortality (HR=2.42, 95%CI: 1.21-4.83), but not breast cancer mortality (HR=0.93, 95%CI: 0.55-1.56). The use of NSAIDs after diagnosis was not associated with all-cause (HR=0.87, 95%CI: 0.69-1.18), breast cancer mortality (HR=0.69, 95%CI: 0.44-1.10), or CVD (HR=0.97, 95%CI: 0.57-1.65).

CONCLUSIONS

The use of antidepressants or NSAIDS was not related to breast cancer mortality in long-term breast cancer survivors. In these women, however, antidepressants may increase the risk of all-cause mortality.

Managing menopausal symptoms and depression in tamoxifen users: implications of drug and medicinal interactions

OBJECTIVE

Tamoxifen, a medication used in the treatment of breast cancer, often induces menopausal symptoms. Certain medications and natural supplements taken or prescribed to alleviate tamoxifen-induced hot flashes and depressive states in women with breast cancer interact with tamoxifen. This paper reviews potentially problematic interactions and offers treatment recommendations.

METHODS

Medline (1950-June 1, 2010), Embase Classic+Embase (1947-June 1, 2010) and PsycINFO (1967-June 1, 2010) were searched through Ovid. The word "tamoxifen" was searched with "depression" and then with "menopaus*" and "symptoms", with "treatment" as a limit. "Tamoxifen" was later searched with the MeSH terms "drug interaction" or "drug incompatibility".

RESULTS

Venlafaxine is efficacious for the treatment of hot flashes and depression and safe to use in combination with tamoxifen. Gabapentin is also efficacious in treating tamoxifen-induced hot flashes and, since it does not interact with cytochrome P450 system, is likely safe to use in patients using tamoxifen. Desvenlafaxine and pregabalin may be alternatives to venlafaxine and gabapentin, respectively, although desvenlafaxine has not yet been studied in this population. Paroxetine, fluoxetine and bupropion are strong CYP2D6 inhibitors which should be avoided in tamoxifen users. Fluvoxamine and nefazodone both inhibit CYP3A, which could potentially affect the metabolism of tamoxifen. Clonidine can be an alternative agent but may carry significant side effects. Evidence of medicinal products for the treatment of tamoxifen-induced hot flashes is equivocal at best.

CONCLUSIONS

Clinicians should remain cautious about using strong inhibitors and/or inducers of cytochrome 2D6 and 3A4 concomitantly with tamoxifen. Use of natural menopausal supplements and diets rich in isoflavones should not be encouraged in tamoxifen users until more data is available. There are however safe treatments for hot flashes and depression in tamoxifen users.

Effect of concomitant CYP2D6 inhibitor use and tamoxifen adherence on breast cancer recurrence in early-stage breast cancer

PURPOSE

The use of cytochrome P450 2D6-inhibiting drugs (CYP2D6 inhibitors) during tamoxifen treatment leads to a decrease in plasma concentration of endoxifen, the major active tamoxifen metabolite. Concomitant use of CYP2D6 inhibitors, such as selective serotonin reuptake inhibitors, as well as low tamoxifen adherence may negatively impact tamoxifen efficacy in patients with breast cancer. The objectives of this study were to relate concomitant CYP2D6 inhibitor use and tamoxifen adherence to breast cancer event-free time (EFT).

PATIENTS AND METHODS

Data were from PHARMO and included a community pharmacy dispensing database; PALGA, a nationwide pathology database; and the Dutch Medical Register in the Netherlands. Patients with breast cancer treated with adjuvant tamoxifen between 1994 and 2006 were included. A Cox proportional hazards model with a time-dependent definition for concomitant CYP2D6 inhibitor exposure was used. Adherence calculated over the first year after tamoxifen initiation was related to breast cancer events in the following period.

RESULTS

In total, 1,962 patients with breast cancer using tamoxifen were included, among whom 150 (7.6%) frequently used a CYP2D6 inhibitor during tamoxifen treatment. No association between concomitant CYP2D6 inhibitor use and breast cancer recurrence was observed (adjusted hazard ratio [HR], 0.87; 95% CI, 0.42 to 1.79; P = .69). Poor tamoxifen adherence was associated with lower EFT (adjusted HR, 0.987; 95% CI, 0.975 to 0.999; P = .029).

CONCLUSION

This observational study did not show an association between concomitant CYP2D6 inhibitor use and breast cancer recurrence among patients treated with adjuvant tamoxifen despite the strong biologic rationale. This study shows, to the best of our knowledge for the first time, that poor tamoxifen adherence is associated with an increased risk of breast cancer events.

Change in lifestyle behaviors and medication use after a diagnosis of ductal carcinoma in situ

Women with ductal carcinoma in situ (DCIS) of the breast represent a growing cancer survivor population with a diagnosis of uncertain malignant potential. These survivors face an absence of scientific guidelines regarding lifestyle changes that can help to prevent a breast cancer recurrence. In this first report from the Wisconsin In Situ Cohort (WISC) study, we examine how women are currently changing their lifestyle behaviors and medication use following a diagnosis of DCIS. At study entry (1997-2006), 1,959 subjects (78% of eligible) with DCIS were identified from the Wisconsin cancer registry and administered an interview assessing behaviors prior to diagnosis. Follow-up interviews were completed every 2 years after the initial interview, beginning in 2003 and continuing through 2006. After adjusting for age and calendar year, women were 2.2 kg (95% CI 1.4, 3.0) heavier, 35% (95% CI 20, 47) less likely to be a smoker, 19% (95% CI -1, 43) more likely to use non-steroidal anti-inflammatory drugs, and 57% (95% CI 26, 95) more likely to use antidepressants after a DCIS diagnosis compared to 1 year prior to diagnosis. Use of postmenopausal hormones decreased sharply (OR = 0.06; 95% CI 0.04, 0.09) following a DCIS diagnosis. These findings indicate that women make substantial changes in their behaviors after a DCIS diagnosis. This cohort will be further monitored to evaluate the association between these behaviors and health outcomes following DCIS.

Selective serotonin reuptake inhibitors and breast cancer mortality in women receiving tamoxifen: a population based cohort study

OBJECTIVE

To characterise whether some selective serotonin reuptake inhibitor (SSRI) antidepressants reduce tamoxifen's effectiveness by inhibiting its bioactivation by cytochrome P450 2D6 (CYP2D6).

DESIGN

Population based cohort study.

PARTICIPANTS

Women living in Ontario aged 66 years or older treated with tamoxifen for breast cancer between 1993 and 2005 who had overlapping treatment with a single SSRI.

MAIN OUTCOME MEASURES

Risk of death from breast cancer after completion of tamoxifen treatment, as a function of the proportion of time on tamoxifen during which each SSRI had been co-prescribed.

RESULTS

Of 2430 women treated with tamoxifen and a single SSRI, 374 (15.4%) died of breast cancer during follow-up (mean follow-up 2.38 years, SD 2.59). After adjustment for age, duration of tamoxifen treatment, and other potential confounders, absolute increases of 25%, 50%, and 75% in the proportion of time on tamoxifen with overlapping use of paroxetine (an irreversible inhibitor of CYP2D6) were associated with 24%, 54%, and 91% increases in the risk of death from breast cancer, respectively (P<0.05 for each comparison). By contrast, no such risk was seen with other antidepressants. We estimate that use of paroxetine for 41% of tamoxifen treatment (the median overlap in our sample) would result in one additional breast cancer death within five years of cessation of tamoxifen for every 19.7 (95% confidence interval 12.5 to 46.3) patients so treated; the risk with more extensive overlap would be greater.

CONCLUSION

Paroxetine use during tamoxifen treatment is associated with an increased risk of death from breast cancer, supporting the hypothesis that paroxetine can reduce or abolish the benefit of tamoxifen in women with breast cancer.

Desipramine inhibits the growth of a mouse skin squamous cell carcinoma cell line and affects glucocorticoid receptor-mediated transcription

The purpose of this study was to examine the effect of tricyclic antidepressant desipramine (DMI) on the growth inhibition and translocation of the glucocorticoid receptor (GR) from the cytoplasm to the nucleus in cancerous and noncancerous cell lines and the effect of DMI on GR-mediated transcription. Nontumorigenic, immortalized keratinocytes cell line (3PC), papilloma (MT1/2), and squamous cell carcinoma (Ca3/7) cell lines were initially used to study the cell growth inhibition by DMI. Although, the growth of all three cell lines was suppressed by DMI, it was more effective in Ca3/7 cells. Therefore, we next examined the effect of DMI on Ca3/7 cells, resistant to growth inhibition by the synthetic glucocorticoid fluocinolone acetonide (FA). DMI inhibited cell proliferation in a time-dependent manner. The translocation of GR was induced by FA alone, DMI alone, and combination of both agents. FA induced GR-mediated transcription in Ca3/7 cells transfected with a luciferase reporter gene under the control of glucocorticoid response element (GRE), but DMI alone did not affect GR-mediated transcription. However, DMI inhibited FA-induced, GR-mediated transcription when both agents were given together. Pretreatment with DMI followed by combination of DMI and FA decreased GR-mediated transcription more than pretreatment with FA. The expression of metallothionein-1 (Mt-1) gene, which is regulated by GR, was induced significantly by the combination of DMI and FA, and enhanced significantly by pretreatment with FA but not DMI. DMI is suggested to inhibit the growth of Ca3/7 cells and to affect GR-mediated transcription.

An indicator of cancer: downregulation of monoamine oxidase-A in multiple organs and species

Background

Identifying consistent changes in cellular function that occur in multiple types of cancer could revolutionize the way cancer is treated. Previous work has produced promising results such as the identification of p53. Recently drugs that affect serotonin reuptake were shown to reduce the risk of colon cancer in man. Here, we analyze an ensemble of cancer datasets focusing on genes involved in the serotonergic pathway. Genechip datasets consisting of cancerous tissue from human, mouse, rat, or zebrafish were extracted from the GEO database. We first compared gene expression between cancerous tissues and normal tissues for each type of cancer and then identified changes that were common to a variety of cancer types.

Results

Our analysis found that significant downregulation of MAO-A, the enzyme that metabolizes serotonin, occurred in multiple tissues from humans, rodents, and fish. MAO-A expression was decreased in 95.4% of human cancer patients and 94.2% of animal cancer cases compared to the non-cancerous controls.

Conclusion

These are the first findings that identify a single reliable change in so many different cancers. Future studies should investigate links between MAO-A suppression and the development of cancer to determine the extent that MAO-A suppression contributes to increased cancer risk.