5 forskare från bla The University of Queensland levererar en riktigt riktigt intressant studie om livmoderhalscancer.Själva studien om denna eländiga cancerform som är den 4:e vanligaste för kvinnor går jag inte in på.Det jag istället vill lyfta fram är vad forskarna åstadkommit och var de fått sina studier publicerade.
Men först en bakgrund om livmoderhalscancer och hur man till dags dato behandlat den.
Cervical cancer är som sagt den 4:e vanligast förekommande hos kvinnor,den är även den 4:e dödsorsaken hos cancerdrabbade kvinnor. Wiki berättar att 528 000 kvinnor drabbades av denna cancer 2012, 266 000 dog i cancern detta år.
Överlevnadsmöjligheterna ökar ju tidigare cancern upptäcks.USA har statistik som beskriver detta enligt 5års överlevnaden.
The 5-year survival rate for all women with cervical cancer is 66%.However, survival rates can vary by factors such as race, ethnicity, and age. For white women, the 5-year survival rates are 71%, and for black women, the 5-year survival rate is 58%. For white women under age 50, the 5-year survival rate is 78%. For black women age 50 and older, the 5-year survival rate is 46%.
Survival rates depend on many factors, including the stage of cervical cancer that is diagnosed.
When detected at an early stage, the 5-year survival rate for women with invasive cervical cancer is 92%.
About 44% of women with cervical cancer are diagnosed at an early stage.
If cervical cancer has spread to surrounding tissues or organs and/or the regional lymph nodes, the 5-year survival rate is 56%.
If the cancer has spread to a distant part of the body, the 5-year survival rate is 17%.
Notera sistnämnda som tydliggör betydelsen av tidig upptäckt och behandling.
Den vaccination som kommit på senare år är inte ett 100% säkert skydd.Därför bör kvinnor gå på kontinuerliga kontroller just in case.Behandlingen utgörs idag av kirurgi,kemoterapi och strålning.Ibland en kombination av dessa.De som behandlats får räkna med komplikationer som oftast är livslånga.
Behovet av bättre behandling mot denna svåra cancer har ofta signalerats från vården. Det lyfter även forskarna fram i sina studier : Recurrent cervical cancer is refractory to currently available treatments. Clearly there is an urgent unmet need to investigate new therapeutic strategies for both the newly diagnosed and recurrent patient populations.
Och då kommer jag till det glädjande beskedet forskarna levererar med denna forskningsrapport.
Till studien betitlitlad :
Smart drug combinations for cervical cancer: dual targeting of Bcl-2 family of proteins and aurora kinases
Studien publiceras i senaste upplagan av American Journal of Cancer Research.Notera att studien redan på förstasidan omnämns.
Abstract
Human papillomavirus (HPV) is the main causative agent in cervical cancers. Recurrent cervical cancer is refractory to currently available treatments. Clearly there is an urgent unmet need to investigate new therapeutic strategies for both the newly diagnosed and recurrent patient populations. We have previously shown that the presence of HPV oncogenes sensitizes cells to inhibition of aurora kinases (AURKs), which induces mitotic delay eventually leading to apoptotic cell death. In this study, we explored whether a dual approach of combining an AURK inhibitor, MLN8237 (Alisertib), with a range of Bcl-2 family anti-apoptotic protein inhibitors would accelerate cancer cell killing. Enhanced and rapid cervical cancer cell killing was observed when Alisertib was combined with inhibitors of either Bcl-2 (Venetoclax), Bcl-XL (A1331852) or Mcl-1 (A1210477) proteins, likely by accelerating apoptosis during mitotic delay due to the loss of functional Bcl-2, Mcl-1, or Bcl-XL. This study presents a promising approach to treating aggressive cervical cancers and may apply to other HPV-related cancers.
Introduction
Human papillomavirus (HPV) is the fourth most prominent cause of cancer in women, the primary cause of cervical cancer. Despite the overwhelming success of HPV vaccines and pap smears, they do not guarantee a lifetime protection against HPV-related cancers and previous exposure prior to vaccination can still lead to the development of cervical carcinomas. Current therapy for cervical cancer involves a combination of surgery, radiotherapy, and chemotherapy that often results in permanent, life-altering adverse effects. We have previously shown that HPV oncogene, E7, sensitizes cells to the inhibition of the aurora kinases (AURKs) and treatment is highly effective at eliminating early tumours and reducing large, late tumours. AURKs have key roles in the transition into, through and out of mitosis. AURKA is required for progression into mitosis and establishing a proper spindle pole, and AURKB is required for exit from mitosis and correct cell division. Functionally, AURKA and B inhibition using MLN8237 (Alisertib) cause HPV positive (+) cells to take longer to traverse mitosis and key anti-apoptotic proteins degrade and apoptosis is induced (1). As we now understand how AURK inhibition affects HPV+ cancer cells, we wish to explore if we can exploit secondary vulnerabilities in cervical cancer cells, using a second molecular inhibitor, to push cells more quickly and effectively towards death. Our previous work showed that Alisertib treatment induces cell death of HPV+ cancer cells via an Mcl-1 sensitive apoptotic mechanism. We also observed that Alisertib treatment had some effect on the expression of other Bcl-2 family members, Bcl-2 and Bcl-XL. Overall, sensitivity to Alisertib was defined by E7 expression and also potentially by the level of Bcl-2 related anti-apoptotic proteins. Therefore, in this study we wish to enhance the effect of Alisertib by adding inhibitors of anti-apoptotic Bcl-2 family of proteins, Bcl-2, Bcl-XL and Mcl-1.
Results and Discussion
To date, no work has been done to assess the effect of combining other drugs with AURK inhibitors (AURKi) in HPV+ cancers. We firstly queried the Cancer Target Discovery and Development (CTD2) (https://ocg.cancer.gov/programs/ctd2) and Genomics of Drug Sensitivity in Cancer (GDSC) (https://www.cancerrxgene.org/) databases to assess any correlation between the level of expression of anti-apoptotic proteins with sensitivity to Alisertib. The cell lines represented in the databases were initially defined as either sensitive or insensitive based on natural inflection points in the drug sensitivity data of all cell lines. The expression levels of the components of the apoptotic machinery, Bcl-2, Bcl-XL, Bcl-W, A1, Mcl-1, Bid, Bim, Bad, Bax, PUMA, NOXA and XIAP genes were assessed. Mcl-1 expression was relatively constant across all cell lines, but Mcl-1 levels are controlled by the E3 ligase, FBXW7 [4], and this was added. It showed that lower levels of the anti-apoptotic Bcl-XL and Bcl-W were significantly associated with increased sensitivity to Alisertib in both datasets (Figure 1A and and1B).1B). Increased FBXW7, suggesting lower Mcl-1 levels, was also associated with sensitivity. Increased pro-apoptotic NOXA, a selective inhibitor of Mcl-1 was associated with sensitivity. Interestingly, a modest decrease in Bad expression, a selective inhibitor of Bcl-2, Bcl-XL and Bcl-W, is also associated with sensitivity. Another mitotically targeted drug, PLK1 inhibitor, BI-2536, showed a similar profile of sensitivity (Figure 1C). Surprisingly, increased Bcl-2 expression was associated with increased sensitivity to both drugs. Unsurprisingly, high Bcl-2 expression is associated with sensitivity to the Bcl-2 inhibitor, Venetoclax (Figure 1D). We have previously reported that Alisertib treatment only affected Mcl-1 (decreased) and Bim (increased) levels. These findings suggested that inhibiting specifically Bcl-2 and Mcl-1 might increase the sensitivity to Alisertib.
In light of this, we explored the effectiveness of combining Alisertib with commercially available inhibitors of Bcl-2 (Venetoclax), Bcl-XL (A1331852) and Mcl-1 (A1210477) on Alisertib-sensitive HPV+ cervical cancer cell lines [1,2], HeLa and CaSki. It is important to note that these cells express varying levels of Bcl-2 proteins (Figure 1E). There was higher Bcl-2 and Mcl-1 and lower Bcl-xL expression in HeLa cells, compared to CaSki cells, consistent with our previous observations [1]. Indeed, combining Alisertib with a range of Bcl-2 family anti-apoptotic protein inhibitors were more effective than inhibitors alone (Figure 1F). Importantly, the effect of combining Alisertib with any of the tested anti-apoptotic protein inhibitors was synergistic (Figure 1G). Dual inhibition of AURKs and Bcl-2 family anti-apoptotic proteins have been explored in other cancer types [5-11], but not HPV+ cancers. Given the premise that AURK inhibition drives cells to undergo apoptosis through the loss of Bcl-2 family expression in other cancer types [12,13], these cells are vulnerable to further inhibition of these Bcl-2 family members.
We then focused on elucidating the onset of cell killing by these dual combinations on HeLa cells. Compared to drugs alone, dual Alisertib and Bcl-2 family anti-apoptotic protein inhibitor combinations shorten the time that cell death events first appeared (Figure 2A), concurring with the occurrence of cells undergoing a smaller number of cell divisions (Figure 2B). Collectively, this suggests that dual combinations induce the rapid onset of cell death. Notably, combination of Alisertib with A1331852 significantly induced cell death as early as 6 hr post-treatment when compared to A1331852 treatment alone (Figure 2C and Supplementary Table 1). Indeed, Alisertib combined with A1331852 produced the most prominent apoptotic killing effect, which is confirmed by higher levels of PARP protein cleavage seen with this combination compared to other combinations (Figure 2D). Co-targeting AURKs and Bcl-2 proteins together has been done in a number of cancer models [14-16]. This is the first study testing this combination for cervical cancers. Enhanced and rapid cervical cancer cell killing observed with this combination likely occurs by accelerating apoptosis during mitotic delay due to the loss of functional Bcl-2 family of proteins. Taken together, our study showed that co-targeting AURK and Bcl-2 family of proteins could represent a novel alternative treatment strategy for cervical cancer. Importantly, this combination could be applied to other HPV-driven cancers. Combination treatment between Alisertib and inhibitors of Bcl-2 family members should be subjected to future clinical trials to overcome specific molecular vulnerabilities in cervical cancer.
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Anti-apoptotic BCL-2 inhibitors accelerate Alisertib-medicated killing. HeLa cells were treated either alone, with Alisertib (500 nM) or in combination with either venetoclax (15 nM), A1331852 (40 nM) or A1210477 (1 nM). A. Anti-apoptotic Bcl-2 inhibitors induce early killing when combined with Alisertib. Images were captured by time-lapse microscopy over 72 h. Still images shown were captured at times indicated. Yellow arrows denote cells that are undergoing cell death. Data presented are representative of one out of three independent experiments. B. Combined drug treatments underwent fewer rounds of mitosis. 10 individual cells were tracked from time-lapse microscopy videos using the Hstudio 2.7.5™ live imaging software and the time in mitosis and number of cell divisions were plotted on the graph over a 72 h period. C. Alisertib combined with anti-apoptotic inhibitors induces early cell death onset. Dead (not double negative for annexin V and propidium iodide) and live (double negative for annexin V and propidium iodide) cell populations were determined by flow cytometry via Annexin V/Propidium Iodide staining at the indicated time points. Percentage of cells are represented on a heat map plot. Data is representative of one out of at least three independent experiments. One-way Anova analysis was done for the 6 h time point to highlight significantly induced cell death seen with the combination of Alisertib with A1331852 (Supplementary Table 1). D. Enhanced killing seen with combined Alisertib and A133185 treatment correlated with elevated PARP cleavage. Proteins from cells collected at 24 h were immunoblotted for cleaved PARP. β-actin was used as a loading control. Individual blots shown are representative of three independent experiments.
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Materials and Methods (urval)
Time-lapse microscopy
Treated cells were followed by time-lapse microscopy using Holometer®, a cell stain-free phase holographic imager (PHI AB, Lund, Sweden) at 37°C and 5% CO2 and data analysed in Hstudio 2.7.5™ (PHI AB, Lund, Sweden) on 24-well plate (STARSTED, Nümbrecht, Germany). Images were captured at 10 min intervals.
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