Professionally led support groups for people living with advanced or metastatic cancer: a systematic scoping review of effectiveness and factors critical to implementation success within real-world healthcare and community settings.

PURPOSE: To examine the effectiveness of professionally led support groups for people with advanced or metastatic cancer, and identify factors critical to implementation success within real-world settings. METHODS: Databases (MEDLINE; PsychINFO; CINAHL) and grey literature were searched for empirical publications and evaluations. Articles were screened for eligibility and data systematically extracted, charted and summarised using a modified scoping review methodology. Implementation factors were mapped using Proctor's implementation framework and the Consolidated Framework for Implementation Research 2.0. RESULTS: A total of 1691 publications were identified; 19 were eligible for inclusion (8 randomised controlled trials, 7 qualitative studies, 2 cohort studies, 2 mixed methods studies). Most (n=18) studies focused on tumour-specific support groups. Evidence supported professionally led support groups in reducing mood disturbances (n=5), distress (i.e. traumatic stress, depression) (n=4) and pain (n=2). Other benefits included social connectedness (n=6), addressing existential distress (n=5), information and knowledge (n=6), empowerment and sense of control (n=2), relationships with families (n=2) and communication with health professionals (n=2). Thirteen studies identified factors predicting successful adoption, implementation or sustainment, including acceptability (n=12; 63%), feasibility (n=6; 32%) and appropriateness (n=1; 5%). Key determinants of successful implementation included group leaders' skills/experience, mode of operation, travelling distance, group composition and membership and resourcing. CONCLUSIONS: Professionally led tumour-specific support groups demonstrate effectiveness in reducing mood disturbances, distress and pain among patients. Successful implementation hinges on factors such as leadership expertise, operational methods and resource allocation. IMPLICATIONS FOR CANCER SURVIVORS: Professionally led support groups may fill an important gap in supportive care for people with advanced or metastatic cancer.

Pegylated siRNA-loaded calcium phosphate nanoparticle-driven amplification of cancer cell internalization in vivo.

The cell membrane is a critical barrier to effective delivery for many therapeutics, including those which are nanoparticle-based. Improving nanoparticle transport across the cell membrane remains a fundamental challenge. Cancer cells preferentially internalized pegylated calcium phosphate nanoparticles over normal epithelial cells. Furthermore, non-cytotoxic levels of doxorubicin markedly amplified this difference by increasing free unbound caveolin-1 and resulted in enhanced caveolin-mediated nanoparticle endocytosis in cancer cells. Engineered pegylated siRNA-loaded triple-shell calcium phosphate nanoconstructs incorporating ultra-low levels of doxorubicin recapitulated these effects and delivered increased numbers of siRNA into cancer cells with target-specific results. Systemic administration of nanoparticles in vivo demonstrated highly preferential entry into tumors, little bystander organ biodistribution, and significant tumor growth arrest. In conclusion, siRNA-loaded calcium phosphate nanoparticles incorporating non-cytotoxic amounts of doxorubicin markedly enhances nanoparticle internalization and results in increased payload delivery with concomitant on-target effects.

Targeting abnormal DNA repair in therapy-resistant breast cancers.

Although hereditary breast cancers have defects in the DNA damage response that result in genomic instability, DNA repair abnormalities in sporadic breast cancers have not been extensively characterized. Recently, we showed that, relative to nontumorigenic breast epithelial MCF10A cells, estrogen receptor-positive (ER+) MCF7 breast cancer cells and progesterone receptor-positive (PR+) MCF7 breast cancer cells have reduced steady-state levels of DNA ligase IV, a component of the major DNA-protein kinase (PK)-dependent nonhomologous end joining (NHEJ) pathway, whereas the steady-state level of DNA ligase IIIα, a component of the highly error-prone alternative NHEJ (ALT NHEJ) pathway, is increased. Here, we show that tamoxifen- and aromatase-resistant derivatives of MCF7 cells and ER(-)/PR(-) cells have even higher steady-state levels of DNA ligase IIIα and increased levels of PARP1, another ALT NHEJ component. This results in increased dependence upon microhomology-mediated ALT NHEJ to repair DNA double-strand breaks (DSB) and the accumulation of chromosomal deletions. Notably, therapy-resistant derivatives of MCF7 cells and ER(-)/PR(-) cells exhibited significantly increased sensitivity to a combination of PARP and DNA ligase III inhibitors that increased the number of DSBs. Biopsies from ER(-)/PR(-) tumors had elevated levels of ALT NHEJ and reduced levels of DNA-PK-dependent NHEJ factors. Thus, our results show that ALT NHEJ is a novel therapeutic target in breast cancers that are resistant to frontline therapies and suggest that changes in NHEJ protein levels may serve as biomarkers to identify tumors that are candidates for this therapeutic approach.