PIK3CA wild-type

Identification of multi-hit PIK3CA GA in CAPC highlights a potentially unique phenotype that may be associated with response to anti-PIK3CA targeted therapy and checkpoint inhibition, supporting relevant clinical trial designs.

The mutated SNP sites in patients with DR were mainly enriched in PI3K/AKT, calcium ion, and glutamatergic synaptic and cholinergic synaptic signaling pathways. The rs17849079 allele of PIK3CA is prone to C/T mutation where the C allele increases the risk of DR. High glucose activates the expression of PIK3CA and promotes the phosphorylation of PI3K, which leads to the phosphorylation of AKT and mTOR. These effects consequently increase VEGF expression and accelerate the development of DR. The C to T allele mutation in PIK3CA.rs17849079 can play a protective role and reduce the risk of DR.

Participants received neoadjuvant paclitaxel with trastuzumab, lapatinib, or both. In ERBB2/HER2-positive EBC, PIK3CA mutations were associated with lower pCR rates and independently associated with worse long-term EFS. These findings appear to be associated with PIK3CA mutations in HR-positive and luminal EBC.

Of the drugs used in second-line chemotherapy for soft tissue sarcoma (STS), trabectedin is effective for liposarcoma and leiomyosarcoma (L-sarcoma), eribulin for liposarcoma, and pazopanib for non-liposarcoma. The present study demonstrated the potential of tailored therapy guided by mutation profiles established by comprehensive genomic profiling testing in optimizing second-line chemotherapy for STS. The findings of this study will hopefully contribute some valuable insights into enhancing STS treatment strategies and outcomes.

P2, N=84, Active, not recruiting, Washington University School of Medicine | Trial completion date: Apr 2027 --> Aug 2026

KRAS wild-type patient resistance may be related to PIK3CA gene mutations, although this needs further verification in larger cohorts. BRAF mutations may be associated with RNF215 expression in patients with CRC.

The SOS1 inhibitor BI-3406 enhanced the efficacy of trametinib and prevented trametinib resistance by targeting spheroid-initiating cells in KRAS-mutated LUAD and COAD cell lines that lacked PIK3CA comutations. Our findings demonstrate that vertical inhibition of RTK/RAS signaling is an effective strategy to prevent therapeutic resistance in KRAS-mutated cancers, but therapeutic efficacy is dependent on both the specific KRAS mutant and underlying comutations. Thus, selection of optimal therapeutic combinations in KRAS-mutated cancers will require a detailed understanding of functional dependencies imposed by allele-specific KRAS mutations.

With the advent of precision oncology, PIK3CA has emerged as a pivotal treatment target, culminating in the recent approval of alpelisib...No significant differences were identified in overall and progression-free survival between the two groups. Our findings enhance the understanding of how PIK3CA mutations shape the clinical and prognostic landscape for breast cancer patients.

These findings suggest that the presence of specific mutations may have implications for predicting the prognosis of breast cancer. Further research and validation are needed to gain a deeper understanding of the role of these mutations and their mechanisms in prognosis prediction.

The secondary endpoints were to decipher the mutation types across breast cancer subtype, menopausal status, and time to treatment failure after everolimus (an mTOR inhibitor) or cyclin-dependent kinase 4/6 (CDK4/6) inhibitor treatment...A high frequency of PIK3CA mutations was detected in Taiwanese patients with breast cancer, which was consistent with previous studies. Early detection of PIK3CA mutations might influence therapeutic decisions, leading to better treatment outcomes.

Significant improvement in targeted therapy for colorectal cancer (CRC) has occurred over the past few decades since the approval of the EGFR inhibitor cetuximab...Inhibition of PIK3CA MT by PI3K inhibitors restored SMI-4a sensitivity in PIK3CA MT CRC cell lines. Taken together, these results demonstrate that sensitivity to SMI-4a is determined by the PIK3CA genotype and that co-targeting of PI3K and PIM1 in PIK3CA MT CRC patients could be a promising and novel therapeutic approach for refractory CRC patients.

P2, N=102, Recruiting, Cancer Institute and Hospital, Chinese Academy of Medical Sciences

This study described real-world aBC subgroups and indicated that the clinical outcomes of subgroups vary. Although PIK3CA hotspot mutations did not lead to inferior survival, they are relevant as possible treatment targets. Overall, these data could be utilized to further evaluate the subgroup-specific medical needs in breast cancer.

Methods We studied a unicentre cohort of 262 patients with steroid hormone receptor-positive, HER2-negative eBC, who were planed to be treated with endocrine therapy only: aromatase inhibitor (AI, n=183) or Tamoxifen (TAM, n=69), AI and TAM (n=9), Fulvestrant (n=1) and tested the three most common somatic PIK3CA gene mutations (H1047R, E545K, E542K) by qPCR. Conclusions Although we observed a trend that AIs are less effective in patients with PIK3CA mutated tumours, formal validation is still lacking. Further data including prospective studies are required.

The HCC1954 and KPL4 cells were chronically exposed to increasing concentrations of alpelisib or to alpelisib + trastuzumab in order to generate derivatives with acquired resistance to alpelisib (AR) and to alpelisib + trastuzumab (ATR). Our findings support the use of an alpha-selective PI3K inhibitor to overcome the therapeutic limitations associated with single or dual HER2 blockade in PIK3CA-mutant HER2+ breast cancer. Future studies are warranted to confirm the potential role of candidate genes/pathways in resistance to alpelisib.

Here, we report a proof- of-concept test case using organoid cultures from metastatic BC specimens to rapidly test drug sensitivity and molecular lesion-driven treatments. Furthermore, establishing specific conditions for the propagation of metastatic material is unprecedented.

We observed that PI3K/PTEN/mTOR pathway is highly dynamic under NACT exposure and the assessment of PIK3CA mutations may capture only a small fraction of such complexity. In this context, mTOR activation trough alternative pathways with respect to PIK3CA signalling may have a crucial role in shaping the molecular landscape of HR+/HER2- BC with RD after NACT. It is imperative to further elucidate the role of PIK3CA and mTOR-dependent pathways in shaping chemoresistance and endocrine resistance in high-risk HR+/HER2- early/locally advanced BC patients.

The backbone of common KRAS and PIK3CA mutations is a rational frame for development of therapeutic algorithms in colorectal cancer and can help guide new drug therapies development. In addition, the prevalence of different molecular groups presented here may help with planning of combination clinical trials by providing estimations of sub-sets with more than one alteration.

Our multiparameter classifier differentially identifies patients who may benefit from HER2-targeted therapy alone from those who need chemotherapy and predicts pCR to anti-HER2 therapy alone comparable to chemotherapy plus dual anti-HER2 therapy in unselected patients.

The embryo of the chicken develops over 21 days and the CAM forms on day 3 to day 4 and serve as a respiratory organ with a rapidly developing vascular system. The CAM assay was performed using four cell lines DLD1 (KRAS/PIK3CA mutated) CACO2 (KRAS/PIK3CA wild-type), LS1034 (KRAS mutated) and SNUC4 (PIK3CA mutated) to demonstrate the anti-tumour effects of Ribociclib (R), Alpelisib (A), the combination of Ribociclib and Alpelisib (R+A) or DMSO as matched vehicle control (VC). The CAM assay is a robust and cost effective in-vivo model. We noted significant both macroscopic and microscopic evidence of best response with the R and A combination as compared to those treated with single agent drugs or DMSO vehicle control was in the CAM xenografts. These findings provide novel insight into a possible therapeutic strategy for patients with relapsed refractory CRC.

A corresponding strong trend of longer PFS in PIK3CA mutated TNBC patients treated with capecitabine was shown.Zusammenfassung: Oncogenic PIK3CA mutations seem to predict PFS benefit in mTNBC cases treated with capecitabine. No correlation between any other genomic event and response to taxanes, PLD or eribulin was observed.

PIK3CA mutations are associated with resistance to NAC but do not affect the response to NAE. Low PTEN expression does not affect response to either NAC or NAE but correlates with shorter RFS in patients who received NAC. These biomarkers will be further evaluated for clinical use to treat postmenopausal luminal breast cancer patients.

The p110α expression was downregulated or not affected in PIK3CA-mutated cell lines, and not significantly upregulated in PIK3CA wild-type cell lines. In conclusion, combination of low-dose metronomic VRL and alpelisib showed synergistic anti-tumor effects and significantly inhibited the growth of HR-positive, HER2-negative, PIK3CA-mutated BC cells, providing a rationale for further efforts to evaluate this combination in vivo.

Our findings indicate that PIK3CA mutation plays a role in oncogenesis in rectal cancer and may be considered as a candidate therapeutic approach targeting the PIK3/Akt/mTOR pathway in patients with residual rectal cancer after NACRT.

Of the 18 patients who achieved 12-week PFS, 12 had left-sided primary tumors, 11 were RAS wild type, 11 were PIK3CA wild type, and 6 had previous regorafenib therapy...Dual inhibition of VEGF plus MET is an attractive therapeutic strategy. This phase II trial demonstrated clinical activity with cabozantinib, a multi-TKI targeting VEGFR2 and MET, in patients with refractory, mCRC.

We previously reported that breast cancer cells lacking protein expression of PIK3R1 had elevated levels of activated MEK, sensitizing them to the MEK inhibitor trametinib. Mutations in PIK3R1 sensitize TNBCs to MEK inhibitors like binimetinib. In the absence of functional PIK3R1, aberrant PI3K signaling occurs, which explains the sensitivity of breast cancers that are PIK3CA wild-type and PIK3R1 mutant to alpelisib. The combination of both MEK and PIK3CA inhibition appears to be an effective combination therapy in TNBCs harboring mutations in PIK3R1.AMA is employed by the U.S. FDA, but contributed to this publication in his own capacity.

UC with PIK3CA missense mutation exhibits a higher immunogenicity through enhancing MHC class I and B2M expression. PIK3CA missense mutation is a potential predictive marker for ICI response in UC.

P2/3; The WSG-ADAPT-TP trial demonstrated that pCR after 12 weeks of chemotherapy-free de-escalated neoadjuvant therapy was associated with excellent survival in HR+/HER2+ EBC without further ACT. Despite higher pCR rates for T-DM1 ± ET versus trastuzumab + ET, all trial arms had similar outcomes because of mandatory standard chemotherapy after non-pCR. WSG-ADAPT-TP demonstrated that such de-escalation trials in HER2+ EBC are feasible and safe for patients. Patient selection on the basis of biomarkers or molecular subtypes may increase the efficacy of systemic chemotherapy-free HER2-targeted approaches.

Background: Tumors harboring 2 or more PIK3CA Short variants (SV) (“Multi-hit”) have been described in breast cancer as linked to enhanced clinical outcome from anti-PIK3CA targeted therapies including alpelisib and investigational agents in clinical trials... Although uncommon, the identification of multi-hit PIK3CA GA in CAPC highlights a potentially unique subtype of this disease that may be associated with enhanced responsiveness to anti-PIK3CA targeted therapy strategies.

Multiple genetic alterations were important reasons for the failure of endocrine therapy for HR-positive and HER2-negative mBC. Targeting these genes might restore the treatment sensitivity and benefit survival.

We demonstrate that pan Bcl-2 family inhibition (ABT-263, rER: 1.52-1.56) or Bcl-xL specific inhibition (WEHI-539, A-1331852; rER: 1.31-2.00) radiosensitized wild-type PIK3CA/PTEN TNBC (MDA-MB-231, CAL-120) but failed to radiosensitize mutant PIK3CA/PTEN TNBC (rER: 0.90 - 1.07; MDA-MB-468, CAL-51, SUM-159). In vivo, ABT-263 or A-1331852 in combination with RT decreased tumor growth and increased tumor tripling time (p < 0.0001) in PIK3CA/PTEN wild-type TNBC cell line and patient-derived xenografts. Collectively, this study provides the preclinical rationale for early phase clinical trials testing the safety, tolerability, and efficacy of Bcl-xL inhibition and RT in women with wild-type PIK3CA/PTEN wild-type TNBC at high risk for recurrence.

Our findings indicate that PIK3CA mutations is significantly associated with a lower rate of pCR when treated with TKI-containing regimens in neoadjuvant chemotherapy of early-stage HER2-positive breast cancer, and is significantly associated with lower ORR and CBR in metastatic HER2-positive breast cancer.

Trametinib in combination with TAS-102 demonstrated a manageable safety profile. However, this combination did not achieve meaningful clinical benefit in patients with RAS-mutated PIK3CA and PTEN wild-type refractory mCRC.

Our findings do not indicate clinical utility for venetoclax plus fulvestrant in endocrine therapy-resistant, CDK4/6 inhibitor-refractory metastatic breast tumors, but suggest possible increased dependence on BCLXL in this setting.

Our study identified PIK3CA mutations as a poor prognostic factor, and our meta-analysis identified PIK3CA mutations as predictive of decreased response to anti-EGFR therapy in patients with mCRC.

Low-dose VRL plus alpelisib showed synergistic anti-tumor effects and significantly inhibited cell viability and proliferation of MCF-7 and T-47D cells. Even lower alpelisib concentrations (10 ng/ml and 100 ng/ml) combined with low-dose metronomic VRL led to a significant reduction of cell viability of PIK3CA -mutated cells, and the anti-tumor activity was comparable with the effects at 1000 ng/ml alpelisib, which is corresponding serum concentration in patients receiving an approved dose of 300 mg/day. Cell viability and proliferation of MDA-MB-231 and BT-549 cells were inhibited by VRL but not by alpelisib alone.

PIK3CA mutation together with c-Met or dMMR/MSI status might be relevant to poor prognosis in BC subsets, especially in Asian women.

Trametinib in combination with TAS-102 demonstrated a manageable safety profile however did not achieve meaningful clinical benefit in patients with RAS-MT and PIK3CA / PTEN-WT refractory mCRC. Research sponsor: Novartis.

Our findings suggest that mODGs harboring PIK3CA mutations have worse OS. Except for an advantage in PFS with TMZ treatment, adjuvant TMZ, radiation, or a combination of the two showed no significant improvement in OS.

Abemaciclib plus fulvestrant was effective regardless of PIK3CA or ESR1 mutation status, with benefit in both PFS and OS, with a numerically greater improvement in median PFS relative to placebo plus fulvestrant for PIK3CA or ESR1-mutant tumors compared to the respective wild-type subgroups, in women with HR+, HER2- ABC that had progressed on ET.

P2, N=35, Active, not recruiting, NSABP Foundation Inc | Recruiting --> Active, not recruiting | Trial completion date: Jan 2022 --> Sep 2022