P-773 Assessment of the putative impact of culture strategies, oocyte/embryo manipulations, and operators: a retrospective analysis of 3705 blastocyst culture cycles and 2604 single blastocyst transfers

Study question

Do the culture strategies, oocyte/embryo manipulations, and operators impact blastulation-rates per cohort of metaphase-II oocytes (BR per MII-oocytes) and/or live-birth-rates per single-embryo-transfer (LBR per SET)?

Summary answer

Undisturbed culture improved the BR per MII-oocytes, while culture drop volumes ≥80ml in the well-of-the-well system were associated with increased LBR per untested/euploid blastocyst SET.

What is known already

IVF lab performance is critical to achieve success in IVF. Yet, while a consensus exists on the main key-performance-indicators (KPIs), namely BR and LBR, and their inherent benchmark values, the strategies to fulfil them are still poorly standardized. The plasticity of human embryos along with the disparities in the patient populations might mask even largely different outcomes across clinics. Therefore, clear guidelines shall outline which procedures to standardize and carefully monitor in IVF laboratories. Here we investigated different embryo culture strategies, manipulations, and operators for their effect on BR and LBR per SET, adjusting the results for all main confounders.

Study design, size, duration

Retrospective analysis of 3705 cycles with ≥1 MII-oocyte and 2604 SETs (January2019-March2021). BR per MII-oocytes and LBR per SET were the main outcomes. Embryo-twinning was also assessed. The putative impact of culture strategies, manipulations, and operators’ expertise (0-5yr,6-11yr or > 12yr) was determined via regression analyses adjusted for possible confounders (autologous/donated oocytes, age, primary/secondary infertility and duration, sperm factor; for SET: also endometrial preparation, age at transfer, number of consecutive transfer, untested/euploid blastocyst, quality, and day).

Participants/materials, setting, methods

In donation cycles, only vitrified oocytes were used. In Preimplantation-Genetic-Testing (PGT) cycles, no assisted-hatching was performed and only euploid non-mosaic vitrified-warmed blastocysts were transferred. The culture strategies assessed were undisturbed (Embryoscope, Geri and Embryoscope-plus)/disturbed (KSystems), volume and approach (drops ≤30ml with single-culture or ≥ 80ml with well-of-the-well approaches), humidified/non-humidified atmosphere and media refreshed/not-refreshed. The manipulations assessed were oocyte/blastocyst vitrification (performed/not-performed), oocyte retrieval and denudation performed with oil overlay (yes/not), laser-assisted artificial-shrinkage (performed/not-performed), trophectoderm biopsy (performed/not-performed).

Main results and the role of chance

The only confounders on BR per MII-oocytes (overall:39.1±26.6%) were sperm factor and oocyte age. The linear regressions showed benefits for humidified atmosphere (unstandardized B-coefficient:+2.9%, p = 0.01), manipulations with oil overlay (+3.9%, p = 0.03) and drops≥80ml with a well-of-the-well approach (+4.3%, p < 0.01). However, only the positive effect of undisturbed incubators was significant when adjusting for confounders [41.7±27.8% (N = 1440 cycles) versus 37.5±25.7% in a disturbed incubator (N = 2265 cycles); unstandardized B-coefficient:+5.6%, 95%CI +3.9% to + 7.3%, standardized beta-coefficient:-0.103,p<0.01].

The main confounders on LBR per SET (overall: N = 1044/2604, 40.1%) were oocyte age, number of consecutive transfer, blastocyst chromosomal status (untested/euploid), quality and day. The univariate logistic regressions showed a benefit for undisturbed incubators (OR:1.3, 95%CI 1.1-1.5, p < 0.01), humidified atmosphere (OR:1.4, 95%CI 1.1-1.7, p < 0.01) and media refresh (OR:1.3, 95% 1.01-1.8, p = 0.05). However, only the use of drops ≥80ml with a well-of-the-well approach rather than drops ≤30ml with a single-culture approach involved an improvement when adjusting for confounders (untested SETs: N = 71/171, 41.5% versus N = 434/1284, 33.8%; euploid SETs: N = 170/316, 53.8% versus N = 369/833, 44.3%; multivariate-OR:1.33, 95%CI 1.12-1.58, adjusted p-value<0.01). This result was confirmed in a sub-analysis across only first patients’ SETs.

Lastly, no feature under investigation was associated with embryo-twinning (overall: N = 23/1243, 1.9% and N = 14/1044, 1.3% per pregnancy and delivery, respectively).

Limitations, reasons for caution

Retrospective single center study. Only ICSI cycles and continuous culture media were assessed. Cleavage stage SETs were excluded. All operators had at least 3yr of experience. Perinatal and gestational outcomes were not evaluated.

Wider implications of the findings

Real-life data adjusted for confounders may unveil fluctuations in critical KPIs mainly imputable to culture strategies. An impact seldom derives from oocyte/embryo manipulations if experienced operators adopt validated protocols. An accurate interpretation of these evidence shall lead to properly designed studies with problem-solving/progress-building purposes, and guidelines to standardize culture practices.

Trial registration number

Not applicable

P–783 Clinical, obstetric and perinatal outcomes after vitrified-warmed euploid blastocyst transfer are independent of cryo-storage duration

Study question

Is cryo-storage duration associated with the outcomes after vitrified-warmed euploid single blastocyst transfer?

Summary answer

Lower live-birth-rates from blastocysts cryo-stored for periods longer than 3-months are mostly imputable to the worse quality of the embryos being warmed across sequential transfers.

What is known already

Blastocyst vitrification is crucial in modern IVF. Given its widespread application, a constant comprehensive monitoring of its effect on reproductive outcomes is pivotal. For instance, the effect of cryo-storage duration on embryo implantation potential, gestational and perinatal outcomes is object of a still ongoing investigation. The evidence in this regard are contrasting especially with regard to similar or decreased live birth rates among blastocysts subject to long-term cryo-storage. When investigating the neonatal outcomes, instead, no impact of blastocyst cryo-storage duration has ever been reported to date. Yet, data on euploid blastocysts and adjusted for quality and full-blastulation day are needed.

Study design, size, duration

Retrospective observational study. We included 2688 vitrified-warmed euploid single blastocyst transfers. The primary outcome was the live-birth-rates (LBR) according to cryo-storage duration clustered as ≤ 60, 61–90, 91–180, 181–360, 361–720, 721–1080 and >1080-days. The secondary outcomes were the miscarriage rate, the rates of gestational and perinatal issues among the deliveries, and the mean gestational age and birthweight among the babies born. All data were adjusted for confounders through linear or logistic regression analyses. Participants/materials, setting, methods: We included all vitrified-warmed transfers (range:1–8) conducted between May–2013 and March–2020 by 1884 patients (age:38±3yr) undergoing one blastocyst stage PGT-A cycle and obtaining ≥1 euploid embryo at our private clinic. Among putative confounders, only the number of sequential transfer from the same patient, blastocyst quality (Gardner’s scheme) and full-blastulation day (5–7) significantly associated with the LBR through univariate regressions. No association was reported for sperm factor, maternal age, incubator, and culture media.

Main results and the role of chance

The LBR of euploid blastocysts cryo-stored for ≤60-days was 49.4% (N = 319/646) versus 48.7% (N = 292/599; OR:0.98,95%CI:0.78–1.21,p=0.82) between 61–90-days, 42.9% (N = 291/679; OR:0.77,95%CI:0.62–0.96,p=0.02) between 91–180-days, 41.7% (N = 169/405; OR:0.73,95%CI:0.57–0.94,p=0.02) between 181–360-days, 34.7% (N = 50/144; OR:0.55,95%CI:0.37–0.79,p<0.01) between 361–720-days, 53.4% (N = 63/118; OR:1.17,95%CI:0.79–1.74,p=0.42) between 721–1080-days, and 50.5% (N = 49/97; OR:1.05,95%CI:0.68–1.60,p=0.83) for >1080-days. However, when these data were adjusted for blastocyst quality and full-blastulation day, all the multivariate-OR were not-significant. Indeed, the longer the cryo-storage period the worse the quality of the euploid blastocysts transferred (e.g. AA-blastocysts were 74% among embryos cryo-stored for ≤90-days, but always <70% for embryos cryo-stored for longer periods, p < 0.01; similarly, day5-blastocysts were ∼50% among embryos cryo-stored for ≤90-days, but always <50% for embryos cryo-stored for longer periods, p = 0.02). The miscarriage-rate (overall 14%, ranging 7–18%) was not associated with cryo-storage duration already from univariate regressions. Also the gestational (overall 6%, ranging 0–8%) and perinatal issues rates (overall 3%, ranging 0–5%) were not associated with cryo-storage duration already from the univariate regressions. Neither the gestational age nor the birthweight showed significant associations with cryo-storage duration, as confirmed by linear regressions. In fact the rate of newborns whose weight was normal-for-gestational-age was similar across all cryo-storage duration groups (overall 81%, ranging 80–83%).

Limitations, reasons for caution

The prevalence of first transfers decreases from ≥95% for procedures conducted ≤90-days from vitrification to 71%, 39%, 22% and 4% for procedures conducted between 91–180, 181–360, 361–720 and >720-days, respectively. However, also the sequential number of transfer was not associated with the LBR when adjusted for blastocyst-quality and full-blastulation day.

Wider implications of the findings: Cryo-storage by vitrification is confirmed safe in the hands of experienced operators, and its duration does not impact any outcome. This information is valuable for freeze-all cycles, but also for women cryo-preserving surplus embryos for second pregnancies; in this regard, 6.8% of the patients in this study delivered ≥2 LBs.

Trial registration number

Not applicable

P-783 Clinical, obstetric and perinatal outcomes after vitrified-warmed euploid blastocyst transfer are independent of cryo-storage duration

Study question

Is cryo-storage duration associated with the outcomes after vitrified-warmed euploid single blastocyst transfer?

Summary answer

Lower live-birth-rates from blastocysts cryo-stored for periods longer than 3-months are mostly imputable to the worse quality of the embryos being warmed across sequential transfers.

What is known already

Blastocyst vitrification is crucial in modern IVF. Given its widespread application, a constant comprehensive monitoring of its effect on reproductive outcomes is pivotal. For instance, the effect of cryo-storage duration on embryo implantation potential, gestational and perinatal outcomes is object of a still ongoing investigation. The evidence in this regard are contrasting especially with regard to similar or decreased live birth rates among blastocysts subject to long-term cryo-storage. When investigating the neonatal outcomes, instead, no impact of blastocyst cryo-storage duration has ever been reported to date. Yet, data on euploid blastocysts and adjusted for quality and full-blastulation day are needed.

Study design, size, duration

Retrospective observational study. We included 2688 vitrified-warmed euploid single blastocyst transfers. The primary outcome was the live-birth-rates (LBR) according to cryo-storage duration clustered as ≤ 60, 61-90, 91-180, 181-360, 361-720, 721-1080 and >1080-days. The secondary outcomes were the miscarriage rate, the rates of gestational and perinatal issues among the deliveries, and the mean gestational age and birthweight among the babies born. All data were adjusted for confounders through linear or logistic regression analyses.

Participants/materials, setting, methods

We included all vitrified-warmed transfers (range:1-8) conducted between May-2013 and March-2020 by 1884 patients (age:38±3yr) undergoing one blastocyst stage PGT-A cycle and obtaining ≥1 euploid embryo at our private clinic. Among putative confounders, only the number of sequential transfer from the same patient, blastocyst quality (Gardner’s scheme) and full-blastulation day (5-7) significantly associated with the LBR through univariate regressions. No association was reported for sperm factor, maternal age, incubator, and culture media.

Main results and the role of chance

The LBR of euploid blastocysts cryo-stored for ≤60-days was 49.4% (N = 319/646) versus 48.7% (N = 292/599; OR:0.98,95%CI:0.78-1.21,p = 0.82) between 61-90-days, 42.9% (N = 291/679; OR:0.77,95%CI:0.62-0.96,p = 0.02) between 91-180-days, 41.7% (N = 169/405; OR:0.73,95%CI:0.57-0.94,p = 0.02) between 181-360-days, 34.7% (N = 50/144; OR:0.55,95%CI:0.37-0.79,p < 0.01) between 361-720-days, 53.4% (N = 63/118; OR:1.17,95%CI:0.79-1.74,p = 0.42) between 721-1080-days, and 50.5% (N = 49/97; OR:1.05,95%CI:0.68-1.60,p = 0.83) for >1080-days. However, when these data were adjusted for blastocyst quality and full-blastulation day, all the multivariate-OR were not-significant. Indeed, the longer the cryo-storage period the worse the quality of the euploid blastocysts transferred (e.g. AA-blastocysts were 74% among embryos cryo-stored for ≤90-days, but always < 70% for embryos cryo-stored for longer periods, p < 0.01; similarly, day5-blastocysts were ∼50% among embryos cryo-stored for ≤90-days, but always < 50% for embryos cryo-stored for longer periods, p = 0.02). The miscarriage-rate (overall 14%, ranging 7-18%) was not associated with cryo-storage duration already from univariate regressions. Also the gestational (overall 6%, ranging 0-8%) and perinatal issues rates (overall 3%, ranging 0-5%) were not associated with cryo-storage duration already from the univariate regressions. Neither the gestational age nor the birthweight showed significant associations with cryo-storage duration, as confirmed by linear regressions. In fact the rate of newborns whose weight was normal-for-gestational-age was similar across all cryo-storage duration groups (overall 81%, ranging 80-83%).

Limitations, reasons for caution

The prevalence of first transfers decreases from ≥95% for procedures conducted ≤90-days from vitrification to 71%, 39%, 22% and 4% for procedures conducted between 91-180, 181-360, 361-720 and >720-days, respectively. However, also the sequential number of transfer was not associated with the LBR when adjusted for blastocyst-quality and full-blastulation day.

Wider implications of the findings

Cryo-storage by vitrification is confirmed safe in the hands of experienced operators, and its duration does not impact any outcome. This information is valuable for freeze-all cycles, but also for women cryo-preserving surplus embryos for second pregnancies; in this regard, 6.8% of the patients in this study delivered ≥2 LBs.

Trial registration number

not applicable

Histologic subtyping affecting outcome of triple negative breast cancer: a large Sardinian population-based analysis

BACKGROUND

Triple Negative breast cancer (TNBC) includes a heterogeneous group of tumors with different clinico-pathological features, molecular alterations and treatment responsivity. Our aim was to evaluate the clinico-pathological heterogeneity and prognostic significance of TNBC histologic variants, comparing "special types" to high-grade invasive breast carcinomas of no special type (IBC-NST).

METHODS

This study was performed on data obtained from TNBC Database, including pathological features and clinical records of 1009 TNBCs patients diagnosed between 1994 and 2015 in the four most important Oncology Units located in different hospitals in Sardinia, Italy. Kaplan-Meier analysis, log-rank test and multivariate Cox proportional-hazards regression were applied for overall survival (OS) and disease free survival (DFS) according to TNBC histologic types.

RESULTS

TNBC "special types" showed significant differences for several clinico-pathological features when compared to IBC-NST. We observed that in apocrine carcinomas as tumor size increased, the number of metastatic lymph nodes manifestly increased. Adenoid cystic carcinoma showed the smallest tumor size relative to IBC-NST. At five-year follow-up, OS was 92.1, 100.0, and 94.5% for patients with apocrine, adenoid cystic and medullary carcinoma, respectively; patients with lobular and metaplastic carcinoma showed the worst OS, with 79.7 and 84.3%, respectively. At ten-years, patients with adenoid cystic (100.0%) and medullary (94.5%) carcinoma showed a favourable prognosis, whereas patients with lobular carcinoma showed the worst prognosis (73.8%). TNBC medullary type was an independent prognostic factor for DFS compared to IBC-NST.

CONCLUSIONS

Our study confirms that an accurate and reliable histopathologic definition of TNBC subtypes has a significant clinical utility and is effective in the therapeutic decision-making process, with the aim to develop innovative and personalized treatments.

MTHFR, XRCC1 and OGG1 genetic polymorphisms in breast cancer: a case-control study in a population from North Sardinia

BACKGROUND

Despite conflicting results, considerable evidence suggests the association between single nucleotide polymorphisms in MTHFR, XRCC1 and OGG1 genes and, risk of developing breast cancer. Here a case-control study is reported, including 135 breat cancer patients and 112 healthy women, all representative of Northern Sardinian population.

METHODS

Polymerase chain reaction/restriction fragment length polymorphism method was used to determine the genotypes of five polymorphisms: MTHFR C677T (rs1801133) and A1298C (rs1801131), XRCC1 Arg194Trp (rs1799782) and Arg399Gln (rs25487) and OGG1 Ser326Cys (rs1052133). Allelic, genotypic and haplotype association analyses with disease risk and clinicopathological parameters were performed.

RESULTS

A nominally significant association with breast cancer risk was observed for MTHFR C677T polymorphism heterozygous genotype in the codominant model (OR: 0.57, 95% CI: 0.32-1.00, p = 0.049) and for Cys/Cys genotype of the OGG1 Ser326Cys polymorphism in the recessive model (OR: 0.23, 95% CI: 0.05-1.11, p = 0.0465). No significant differences were found at genotype-level for A1298C polymorphism of the MTHFR gene and Arg194Trp and Arg399Gln of the XRCC1 gene. Furthermore, the OGG1 and XRCC1 rs25487 polymorphisms were nominally associated with PgR, Her2 status and with sporadic breast cancer, respectively.

CONCLUSIONS

Based on genetic characteristics of individuals included in this study, results suggest that MTHFR CT and OGG1 Cys/Cys genotypes have a protective effect that may have an influence on breast cancer risk in a representative Northern Sardinian population.

Antiproliferative and proapoptotic effects of Inula viscosa extract on Burkitt lymphoma cell line

Burkitt lymphoma is a very aggressive B-cell non-Hodgkin lymphoma. Although remarkable progress has been made in the therapeutic scenario for patients with Burkitt lymphoma, search and development of new effective anticancer agents to improve patient outcome and minimize toxicity has become an urgent issue. In this study, the antitumoral activity of Inula viscosa, a traditional herb obtained from plants collected on the Asinara Island, Italy, was evaluated in order to explore potential antineoplastic effects of its metabolites on Burkitt lymphoma. Raji human cell line was treated with increasing Inula viscosa extract concentration for cytotoxicity screening and subsequent establishment of cell cycle arrest and apoptosis. Moreover, gene expression profiles were performed to identify molecular mechanisms involved in the anticancer activities of this medical plant. The Inula viscosa extract exhibited powerful antiproliferative and cytotoxic activities on Raji cell line, showing a dose- and time-dependent decrease in cell viability, obtained by cell cycle arrest in the G2/M phase and an increase in cell apoptosis. The treatment with Inula viscosa caused downregulation of genes involved in cell cycle and proliferation (c-MYC, CCND1) and inhibition of cell apoptosis (BCL2, BCL2L1, BCL11A). The Inula viscosa extract causes strong anticancer effects on Burkitt lymphoma cell line. The molecular mechanisms underlying such antineoplastic activity are based on targeting and downregulation of genes involved in cell cycle and apoptosis. Our data suggest that Inula viscosa natural metabolites should be further exploited as potential antineoplastic agents against Burkitt lymphoma.

Integrated Analysis of miRNA and mRNA Endorses a Twenty miRNAs Signature for Colorectal Carcinoma

Colorectal cancer (CRC) ranks as the most frequent carcinoma worldwide. CRC patients show strong prognostic differences and responses to treatment, and 20% have incurable metastatic disease at diagnosis. We considered it essential to investigate mechanisms that control cellular regulatory networks, such as the miRNA-mRNA interaction, known to be involved in cancer pathogenesis. We conducted a human miRNome analysis by TaqMan low density array, comparing CRC to normal colon tissue (NCT, and experimentally identified gene targets of miRNAs deregulated, by anti-correlation analysis, with the CRC whole-transcriptome profile obtained from RNASeq experiments. We identified an integrated signature of 20 deregulated miRNAs in CRC. Enrichment analyses of the gene targets controlled by these miRNAs brought to light 25 genes, members of pathways known to lead to cell growth and death (CCND1, NKD1, FZD3, MAD2L1, etc.), such as cell metabolism (ACSL6, PRPS1-2). A screening of prognosis-mediated miRNAs underlined that the overexpression of miR-224 promotes CRC metastasis, and is associated with high stage and poor survival. These findings suggest that the biology and progression of CRC depend on deregulation of multiple miRNAs that cause a complex dysfunction of cellular molecular networks. Our results have further established miRNA-mRNA interactions and defined multiple pathways involved in CRC pathogenesis.

Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms in breast cancer: a Sardinian preliminary case-control study

Two common polymorphisms in the MTHFR gene, C677T and A1298C, are associated with reduced enzyme activity and may be associated with breast cancer susceptibility. We performed a case-control study to investigate the association between the two SNPs in the MTHFR gene and risk of breast cancer. In total, 58 breast cancer patients and 58 unaffected controls were enrolled in the study. Polymerase chain reaction/restriction fragment length polymorphism technique (PCR-RFLP) was conducted to determine the genotypes. No significant differences were found in the genotypes of the two polymorphisms of the MTHFR gene between cases and controls. The OR and 95% CI for the 677CC, 677CT and 677TT genotypes were 1.00, 0.95 (0.39-2.31) and 0.87 (0.27-2.80), respectively; those of the 1298AA, 1298AC and 1298CC genotypes were 1.00, 0.59 (0.26-1.36) and 0.78 (1.32-4.66) respectively. Furthermore, it has been shown in patients with breast cancer a risk of presenting with an aggressive biophenotype about twice or three times higher in the presence of the C677T and A1298C polymorphisms, respectively. Finally, the A1298Cpolymorphism is significantly associated with increased recurrence risk of lymph node-positive breast cancer. Our study has not shown a significant association between MTHFR gene polymorphisms and breast cancer risk. However, it highlighted the key-role played by the presence of mutant alleles for both polymorphisms in increasing the risk of developing more aggressive phenotypes; moreover, specifically in A1298C, it might also lead to a higher risk of developing lymph node metastasis.

MicroRNA-425-5p Expression Affects BRAF/RAS/MAPK Pathways In Colorectal Cancers

Colorectal cancer (CRC) is a leading cause of cancer death worldwide and about 20% is metastatic at diagnosis and untreatable. The anti-EGFR therapy in metastatic patients is led by the presence of KRAS-mutations in tumor tissue. KRAS-wild-type CRC patients showed a positive response rate of about 70% to cetuximab or panitumumab combined with chemotherapy. MiRNAs are promising markers in oncology and could improve our knowledge on pathogenesis and drug resistance in CRC patients. This class of molecules represents an opportunity for the development of miRNA-based strategies to overcome the ineffectiveness of anti-EGFR therapy. We performed an integrative analysis of miRNA expression profile between KRAS-mutated CRC and KRAS-wildtype CRC and paired normal colic tissue (NCT). We revealed an overexpression of miR-425-5p in KRAS-mutated CRC compared to KRAS-wild type CRC and NCT and demonstrated that miR-425-5p exerts regulatory effects on target genes involved in cellular proliferation, migration, invasion, apoptosis molecular networks. These epigenetic mechanisms could be responsible of the strong aggressiveness of KRAS-mutated CRC compared to KRAS-wildtype CRC. We proved that some miR-425-5p targeted genes are involved in EGFR tyrosine kinase inhibitor resistance pathway, suggesting that therapies based on miR-425-5p may have strong potential in targeting KRAS-driven CRC. Moreover, we demonstrated a role in the oncogenesis of miR-31-5p, miR-625-5p and miR-579 by comparing CRC versus NCT. Our results underlined that miR-425-5p might act as an oncogene to participate in the pathogenesis of KRAS-mutated CRC and contribute to increase the aggressiveness of this subcategory of CRC, controlling a complex molecular network.

Clinical and pathological factors influencing survival in a large cohort of triple-negative breast cancer patients

BACKGROUND

To provide further information on the clinical and pathological prognostic factors in triple-negative breast cancer (TNBC), for which limited and inconsistent data are available.

METHODS

Pathological characteristics and clinical records of 841 TNBCs diagnosed between 1994 and 2015 in four major oncologic centers from Sardinia, Italy, were reviewed. Multivariate hazard ratios (HRs) for mortality and recurrence according to various clinicopathological factors were estimated using Cox proportional hazards models.

RESULTS

After a mean follow-up of 4.3 years, 275 (33.3%) TNBC patients had a progression of the disease and 170 (20.2%) died. After allowance for study center, age at diagnosis, and various clinicopathological factors, all components of the TNM staging system were identified as significant independent prognostic factors for TNBC mortality. The HRs were 3.13, 9.65, and 29.0, for stage II, III and IV, respectively, vs stage I. Necrosis and Ki-67 > 16% were also associated with increased mortality (HR: 1.61 and 1.99, respectively). Patients with tumor histotypes other than ductal invasive/lobular carcinomas had a more favorable prognosis (HR: 0.40 vs ductal invasive carcinoma). No significant associations with mortality were found for histologic grade, tumor infiltrating lymphocytes, and lymphovascular invasion. Among lymph node positive TNBCs, lymph node ratio appeared to be a stronger predictor of mortality than pathological lymph nodes stage (HR: 0.80 for pN3 vs pN1, and 3.05 for >0.65 vs <0.21 lymph node ratio), respectively. Consistent results were observed for cancer recurrence, except for Ki-67 and necrosis that were not found to be significant predictors for recurrence.

CONCLUSIONS

This uniquely large study of TNBC patients provides further evidence that, besides tumor stage at diagnosis, lymph node ratio among lymph node positive tumors is an additional relevant predictor of survival and tumor recurrence, while Ki-67 seems to be predictive of mortality, but not of recurrence.

miRNA-135b Contributes to Triple Negative Breast Cancer Molecular Heterogeneity: Different Expression Profile in Basal-like Versus non-Basal-like Phenotypes

The clinical and genetic heterogeneity of Triple Negative Breast Cancer (TNBC) and the lack of unambiguous molecular targets contribute to the inadequacy of current therapeutic options for these variants. MicroRNAs (miRNA) are a class of small highly conserved regulatory endogenous non-coding RNA, which can alter the expression of genes encoding proteins and may play a role in the dysregulation of cellular pathways. Our goal was to improve the knowledge of the molecular pathogenesis of TNBC subgroups analyzing the miRNA expression profile, and to identify new prognostic and predictive biomarkers. We conducted a human miRNome analysis by TaqMan Low Density Array comparing different TNBC subtypes, defined by immunohistochemical basal markers EGFR and CK5/6. RT-qPCR confirmed differential expression of microRNAs. To inspect the function of the selected targets we perform Gene Ontology and KEGG enrichment analysis. We identified a single miRNA signature given by miR-135b expression level, which was strictly related to TNBC with basal-like phenotype. miR-135b target analysis revealed a role in the TGF-beta, WNT and ERBB pathways. A significant positive correlation was identified between neoplastic proliferative index and miR-135b expression. These findings confirm the oncogenic roles of miR-135b in the pathogenesis of TNBC expressing basal markers. A potential negative prognostic role of miR-135b overexpression might be related to the positive correlation with high proliferative index. Our study implies potential clinical applications: miR-135b could be a potential therapeutic target in basal-like TNBCs.

EGFR kinase-dependent and kinase-independent roles in clear cell renal cell carcinoma

Epidermal growth factor receptor (EGFR) is associated with progression of many epithelial malignancies and represents a significant therapeutic target. Although clear cell renal cell carcinoma (CCRCC) has been widely investigated for EGFR molecular alterations, genetic evidences of EGFR gene activating mutations and/or gene amplification have been rarely confirmed in the literature. Therefore, until now EGFR-targeted therapies in clinical trials have been demonstrated unsuccessful. New evidence has been given about the interactions between EGFR and the sodium glucose co-transporter-1 (SGLT1) in maintaining the glucose basal intracellular level to favour cancer cell growth and survival; thus a new functional role may be attributed to EGFR, regardless of its kinase activity. To define the role of EGFR in CCRCC an extensive investigation of genetic changes and functional kinase activities was performed in a series of tumors by analyzing the EGFR mutational status and expression profile, together with the protein expression of downstream signaling pathways members. Furthermore, we investigated the co-expression of EGFR and SGLT1 proteins and their relationships with clinic-pathological features in CCRCC. EGFR protein expression was identified in 98.4% of CCRCC. Furthermore, it was described for the first time that SGLT1 is overexpressed in CCRCC (80.9%), and that co-expression with EGFR is appreciable in 79.4% of the tumours. Moreover, the activation of downstream EGFR pathways was found in about 79.4% of SGLT1-positive CCRCCs. The mutational status analysis of EGFR failed to demonstrate mutations on exons 18 to 24 and the presence of EGFR-variantIII (EGFRvIII) in all CCRCCs analyzed. FISH analysis revealed absence of EGFR amplification, and high polysomy of chromosome 7. Finally, the EGFR gene expression profile showed gene overexpression in 38.2% of CCRCCs. Our study contributes to define the complexity of EGFR role in CCRCC, identifying its bivalent kinase-dependent and kinase-independent functions, both potentially involved in CCRCC progression. These results might have important implications on therapeutic approaches to CCRCC, since the disruption of the interaction between EGFR/SGLT1, mediated by anti-EGFR antibodies and/or SGLT1 inhibitors, might constitute a novel therapeutic target for CCRCC treatment, and new clinical trials should be evaluated on the basis of this therapeutic proposal.

Analysis of PIK3CA Mutations and Activation Pathways in Triple Negative Breast Cancer

Background

Triple Negative Breast Cancer (TNBC) accounts for 12–24% of all breast carcinomas, and shows worse prognosis compared to other breast cancer subtypes. Molecular studies demonstrated that TNBCs are a heterogeneous group of tumors with different clinical and pathologic features, prognosis, genetic-molecular alterations and treatment responsivity. The PI3K/AKT is a major pathway involved in the regulation of cell survival and proliferation, and is the most frequently altered pathway in breast cancer, apparently with different biologic impact on specific cancer subtypes. The most common genetic abnormality is represented by PIK3CA gene activating mutations, with an overall frequency of 20–40%. The aims of our study were to investigate PIK3CA gene mutations on a large series of TNBC, to perform a wider analysis on genetic alterations involving PI3K/AKT and BRAF/RAS/MAPK pathways and to correlate the results with clinical-pathologic data.

Materials and Methods

PIK3CA mutation analysis was performed by using cobas® PIK3CA Mutation Test. EGFR, AKT1, BRAF, and KRAS genes were analyzed by sequencing. Immunohistochemistry was carried out to identify PTEN loss and to investigate for PI3K/AKT pathways components.

Results

PIK3CA mutations were detected in 23.7% of TNBC, whereas no mutations were identified in EGFR, AKT1, BRAF, and KRAS genes. Moreover, we observed PTEN loss in 11.3% of tumors. Deregulation of PI3K/AKT pathways was revealed by consistent activation of pAKT and p-p44/42 MAPK in all PIK3CA mutated TNBC.

Conclusions

Our data shows that PIK3CA mutations and PI3K/AKT pathway activation are common events in TNBC. A deeper investigation on specific TNBC genomic abnormalities might be helpful in order to select patients who would benefit from current targeted therapy strategies.