Inclusion Criteria:

          -  Disease Characteristics - Breast, Prostate, and Lung Cancer

               -  Part 1A (Monotherapy Dose Escalation) Histological or cytological diagnosis of
                  locally advanced or metastatic ER+HER2- breast cancer, locally advanced or
                  metastatic CRPC, or locally advanced or metastatic NSCLC that is intolerant or
                  resistant to standard therapy or for which no standard therapy is available.

               -  Part 1B and Part 1C (Combination Dose Escalation) Histological or cytological
                  diagnosis of locally advanced or metastatic ER+HER2- breast cancer. Participants
                  must have progressed after at least 1 prior line of treatment with an endocrine
                  therapy and CDK4/6 inhibitor in the advanced or metastatic setting.

               -  Part 2A (ER+HER2- breast cancer 3L+, monotherapy) Histological or cytological
                  diagnosis of locally advanced or metastatic ER+HER2- breast cancer. Participants
                  must have progressed after at least 1 prior line of CDK4/6 inhibitor and 2 lines
                  of endocrine therapy.

               -  Part 2B (ER+HER2- breast cancer 2L, combination) Histological or cytological
                  diagnosis of locally advanced or metastatic ER+HER2- breast cancer. Participants
                  must have progressed after first line combination treatment with letrozole +
                  palbociclib.

               -  Participants with ER+HER2- advanced or metastatic breast cancer must have
                  documentation of ER-positive tumor (≥1% positive stained cells) based on most
                  recent tumor biopsy utilizing an assay consistent with local standards.

               -  Participants with ER+HER2- advanced or metastatic breast cancer must have
                  documentation of HER2-negative tumor: HER2-negative tumor is determined as
                  immunohistochemistry score 0/1+ or negative by in situ hybridization
                  (FISH/CISH/SISH/DISH) defined as a HER2/CEP17 ratio <2 or for single probe
                  assessment a HER2 copy number <4.

               -  Female participants with ER+HER2- advanced or metastatic breast cancer considered
                  to be of childbearing potential (or have tubal ligations only) must be willing to
                  undergo medically induced menopause by treatment with the approved LHRH agonist
                  such as goserelin, leuprolide or equivalent agents to induce chemical menopause.

               -  Participants must have at least 1 measurable lesion as defined by RECIST version
                  1.1 that has not been previously irradiated.

               -  Eastern Cooperative Oncology Group (ECOG) Performance Status PS 0 or 1

               -  Female or male patients aged ≥ 18 years (Japan ≥ 20 years).

               -  Adequate renal, liver, and bone marrow function.

               -  Resolved acute effects of any prior therapy to baseline severity or CTCAE Grade 1
                  except for adverse events (AEs) not constituting a safety risk by investigator
                  judgment.

        Exclusion Criteria:

          -  Unmanageable ascites (limited medical treatment to control ascites is permitted, but
             all participants with ascites require review by sponsor's medical monitor).

          -  Participants with any other active malignancy within 3 years prior to enrollment,
             except for adequately treated basal cell or squamous cell skin cancer, or carcinoma in
             situ.

          -  Major surgery, radiation therapy, or systemic anti-cancer therapy within 4 weeks prior
             to study entry.

          -  Prior irradiation to >25% of the bone marrow.

          -  ECG clinically relevant abnormalities (eg, QTc >470 msec, complete LBBB, second/third
             degree AV block, ST elevation or EKG changes suggesting myocardial infarction or
             active myocardia ischemia).

          -  Therapeutic anticoagulation. However, low molecular weight heparin is allowed. Vitamin
             K antagonists or factor Xa inhibitors may be allowed following discussion with the
             Sponsor.

          -  Known or suspected hypersensitivity or severe allergy to active ingredient/excipients
             of PF-07248144.

          -  Active inflammatory GI disease, refractory and unresolved chronic diarrhea or previous
             gastric resection, lap band surgery or other GI conditions and surgeries that may
             significantly alter the absorption of PF-07248144 tablets. Gastroesophageal reflux
             disease under treatment is allowed.

          -  Pregnant or breastfeeding female participants.